Adding upstream version 6.1.76.upstream/6.1.76

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 2951 insertions, 0 deletions

diff --git a/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
new file mode 100644
index 000000000..260e6a331
--- /dev/null
+++ b/drivers/gpu/drm/amd/amdgpu/amdgpu_amdkfd_gpuvm.c
@@ -0,0 +1,2951 @@
+// SPDX-License-Identifier: MIT
+/*
+ * Copyright 2014-2018 Advanced Micro Devices, Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE COPYRIGHT HOLDER(S) OR AUTHOR(S) BE LIABLE FOR ANY CLAIM, DAMAGES OR
+ * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+ * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
+ * OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include <linux/dma-buf.h>
+#include <linux/list.h>
+#include <linux/pagemap.h>
+#include <linux/sched/mm.h>
+#include <linux/sched/task.h>
+
+#include "amdgpu_object.h"
+#include "amdgpu_gem.h"
+#include "amdgpu_vm.h"
+#include "amdgpu_amdkfd.h"
+#include "amdgpu_dma_buf.h"
+#include <uapi/linux/kfd_ioctl.h>
+#include "amdgpu_xgmi.h"
+#include "kfd_smi_events.h"
+
+/* Userptr restore delay, just long enough to allow consecutive VM
+ * changes to accumulate
+ */
+#define AMDGPU_USERPTR_RESTORE_DELAY_MS 1
+
+/*
+ * Align VRAM availability to 2MB to avoid fragmentation caused by 4K allocations in the tail 2MB
+ * BO chunk
+ */
+#define VRAM_AVAILABLITY_ALIGN (1 << 21)
+
+/* Impose limit on how much memory KFD can use */
+static struct {
+	uint64_t max_system_mem_limit;
+	uint64_t max_ttm_mem_limit;
+	int64_t system_mem_used;
+	int64_t ttm_mem_used;
+	spinlock_t mem_limit_lock;
+} kfd_mem_limit;
+
+static const char * const domain_bit_to_string[] = {
+		"CPU",
+		"GTT",
+		"VRAM",
+		"GDS",
+		"GWS",
+		"OA"
+};
+
+#define domain_string(domain) domain_bit_to_string[ffs(domain)-1]
+
+static void amdgpu_amdkfd_restore_userptr_worker(struct work_struct *work);
+
+static bool kfd_mem_is_attached(struct amdgpu_vm *avm,
+		struct kgd_mem *mem)
+{
+	struct kfd_mem_attachment *entry;
+
+	list_for_each_entry(entry, &mem->attachments, list)
+		if (entry->bo_va->base.vm == avm)
+			return true;
+
+	return false;
+}
+
+/* Set memory usage limits. Current, limits are
+ *  System (TTM + userptr) memory - 15/16th System RAM
+ *  TTM memory - 3/8th System RAM
+ */
+void amdgpu_amdkfd_gpuvm_init_mem_limits(void)
+{
+	struct sysinfo si;
+	uint64_t mem;
+
+	si_meminfo(&si);
+	mem = si.freeram - si.freehigh;
+	mem *= si.mem_unit;
+
+	spin_lock_init(&kfd_mem_limit.mem_limit_lock);
+	kfd_mem_limit.max_system_mem_limit = mem - (mem >> 4);
+	kfd_mem_limit.max_ttm_mem_limit = (mem >> 1) - (mem >> 3);
+	pr_debug("Kernel memory limit %lluM, TTM limit %lluM\n",
+		(kfd_mem_limit.max_system_mem_limit >> 20),
+		(kfd_mem_limit.max_ttm_mem_limit >> 20));
+}
+
+void amdgpu_amdkfd_reserve_system_mem(uint64_t size)
+{
+	kfd_mem_limit.system_mem_used += size;
+}
+
+/* Estimate page table size needed to represent a given memory size
+ *
+ * With 4KB pages, we need one 8 byte PTE for each 4KB of memory
+ * (factor 512, >> 9). With 2MB pages, we need one 8 byte PTE for 2MB
+ * of memory (factor 256K, >> 18). ROCm user mode tries to optimize
+ * for 2MB pages for TLB efficiency. However, small allocations and
+ * fragmented system memory still need some 4KB pages. We choose a
+ * compromise that should work in most cases without reserving too
+ * much memory for page tables unnecessarily (factor 16K, >> 14).
+ */
+
+#define ESTIMATE_PT_SIZE(mem_size) max(((mem_size) >> 14), AMDGPU_VM_RESERVED_VRAM)
+
+/**
+ * amdgpu_amdkfd_reserve_mem_limit() - Decrease available memory by size
+ * of buffer.
+ *
+ * @adev: Device to which allocated BO belongs to
+ * @size: Size of buffer, in bytes, encapsulated by B0. This should be
+ * equivalent to amdgpu_bo_size(BO)
+ * @alloc_flag: Flag used in allocating a BO as noted above
+ *
+ * Return: returns -ENOMEM in case of error, ZERO otherwise
+ */
+int amdgpu_amdkfd_reserve_mem_limit(struct amdgpu_device *adev,
+		uint64_t size, u32 alloc_flag)
+{
+	uint64_t reserved_for_pt =
+		ESTIMATE_PT_SIZE(amdgpu_amdkfd_total_mem_size);
+	size_t system_mem_needed, ttm_mem_needed, vram_needed;
+	int ret = 0;
+
+	system_mem_needed = 0;
+	ttm_mem_needed = 0;
+	vram_needed = 0;
+	if (alloc_flag & KFD_IOC_ALLOC_MEM_FLAGS_GTT) {
+		system_mem_needed = size;
+		ttm_mem_needed = size;
+	} else if (alloc_flag & KFD_IOC_ALLOC_MEM_FLAGS_VRAM) {
+		/*
+		 * Conservatively round up the allocation requirement to 2 MB
+		 * to avoid fragmentation caused by 4K allocations in the tail
+		 * 2M BO chunk.
+		 */
+		vram_needed = size;
+	} else if (alloc_flag & KFD_IOC_ALLOC_MEM_FLAGS_USERPTR) {
+		system_mem_needed = size;
+	} else if (!(alloc_flag &
+				(KFD_IOC_ALLOC_MEM_FLAGS_DOORBELL |
+				 KFD_IOC_ALLOC_MEM_FLAGS_MMIO_REMAP))) {
+		pr_err("%s: Invalid BO type %#x\n", __func__, alloc_flag);
+		return -ENOMEM;
+	}
+
+	spin_lock(&kfd_mem_limit.mem_limit_lock);
+
+	if (kfd_mem_limit.system_mem_used + system_mem_needed >
+	    kfd_mem_limit.max_system_mem_limit)
+		pr_debug("Set no_system_mem_limit=1 if using shared memory\n");
+
+	if ((kfd_mem_limit.system_mem_used + system_mem_needed >
+	     kfd_mem_limit.max_system_mem_limit && !no_system_mem_limit) ||
+	    (kfd_mem_limit.ttm_mem_used + ttm_mem_needed >
+	     kfd_mem_limit.max_ttm_mem_limit) ||
+	    (adev && adev->kfd.vram_used + vram_needed >
+	     adev->gmc.real_vram_size - reserved_for_pt)) {
+		ret = -ENOMEM;
+		goto release;
+	}
+
+	/* Update memory accounting by decreasing available system
+	 * memory, TTM memory and GPU memory as computed above
+	 */
+	WARN_ONCE(vram_needed && !adev,
+		  "adev reference can't be null when vram is used");
+	if (adev) {
+		adev->kfd.vram_used += vram_needed;
+		adev->kfd.vram_used_aligned += ALIGN(vram_needed, VRAM_AVAILABLITY_ALIGN);
+	}
+	kfd_mem_limit.system_mem_used += system_mem_needed;
+	kfd_mem_limit.ttm_mem_used += ttm_mem_needed;
+
+release:
+	spin_unlock(&kfd_mem_limit.mem_limit_lock);
+	return ret;
+}
+
+void amdgpu_amdkfd_unreserve_mem_limit(struct amdgpu_device *adev,
+		uint64_t size, u32 alloc_flag)
+{
+	spin_lock(&kfd_mem_limit.mem_limit_lock);
+
+	if (alloc_flag & KFD_IOC_ALLOC_MEM_FLAGS_GTT) {
+		kfd_mem_limit.system_mem_used -= size;
+		kfd_mem_limit.ttm_mem_used -= size;
+	} else if (alloc_flag & KFD_IOC_ALLOC_MEM_FLAGS_VRAM) {
+		WARN_ONCE(!adev,
+			  "adev reference can't be null when alloc mem flags vram is set");
+		if (adev) {
+			adev->kfd.vram_used -= size;
+			adev->kfd.vram_used_aligned -= ALIGN(size, VRAM_AVAILABLITY_ALIGN);
+		}
+	} else if (alloc_flag & KFD_IOC_ALLOC_MEM_FLAGS_USERPTR) {
+		kfd_mem_limit.system_mem_used -= size;
+	} else if (!(alloc_flag &
+				(KFD_IOC_ALLOC_MEM_FLAGS_DOORBELL |
+				 KFD_IOC_ALLOC_MEM_FLAGS_MMIO_REMAP))) {
+		pr_err("%s: Invalid BO type %#x\n", __func__, alloc_flag);
+		goto release;
+	}
+	WARN_ONCE(adev && adev->kfd.vram_used < 0,
+		  "KFD VRAM memory accounting unbalanced");
+	WARN_ONCE(kfd_mem_limit.ttm_mem_used < 0,
+		  "KFD TTM memory accounting unbalanced");
+	WARN_ONCE(kfd_mem_limit.system_mem_used < 0,
+		  "KFD system memory accounting unbalanced");
+
+release:
+	spin_unlock(&kfd_mem_limit.mem_limit_lock);
+}
+
+void amdgpu_amdkfd_release_notify(struct amdgpu_bo *bo)
+{
+	struct amdgpu_device *adev = amdgpu_ttm_adev(bo->tbo.bdev);
+	u32 alloc_flags = bo->kfd_bo->alloc_flags;
+	u64 size = amdgpu_bo_size(bo);
+
+	amdgpu_amdkfd_unreserve_mem_limit(adev, size, alloc_flags);
+
+	kfree(bo->kfd_bo);
+}
+
+/**
+ * @create_dmamap_sg_bo: Creates a amdgpu_bo object to reflect information
+ * about USERPTR or DOOREBELL or MMIO BO.
+ * @adev: Device for which dmamap BO is being created
+ * @mem: BO of peer device that is being DMA mapped. Provides parameters
+ *	 in building the dmamap BO
+ * @bo_out: Output parameter updated with handle of dmamap BO
+ */
+static int
+create_dmamap_sg_bo(struct amdgpu_device *adev,
+		 struct kgd_mem *mem, struct amdgpu_bo **bo_out)
+{
+	struct drm_gem_object *gem_obj;
+	int ret, align;
+
+	ret = amdgpu_bo_reserve(mem->bo, false);
+	if (ret)
+		return ret;
+
+	align = 1;
+	ret = amdgpu_gem_object_create(adev, mem->bo->tbo.base.size, align,
+			AMDGPU_GEM_DOMAIN_CPU, AMDGPU_GEM_CREATE_PREEMPTIBLE,
+			ttm_bo_type_sg, mem->bo->tbo.base.resv, &gem_obj);
+
+	amdgpu_bo_unreserve(mem->bo);
+
+	if (ret) {
+		pr_err("Error in creating DMA mappable SG BO on domain: %d\n", ret);
+		return -EINVAL;
+	}
+
+	*bo_out = gem_to_amdgpu_bo(gem_obj);
+	(*bo_out)->parent = amdgpu_bo_ref(mem->bo);
+	return ret;
+}
+
+/* amdgpu_amdkfd_remove_eviction_fence - Removes eviction fence from BO's
+ *  reservation object.
+ *
+ * @bo: [IN] Remove eviction fence(s) from this BO
+ * @ef: [IN] This eviction fence is removed if it
+ *  is present in the shared list.
+ *
+ * NOTE: Must be called with BO reserved i.e. bo->tbo.resv->lock held.
+ */
+static int amdgpu_amdkfd_remove_eviction_fence(struct amdgpu_bo *bo,
+					struct amdgpu_amdkfd_fence *ef)
+{
+	struct dma_fence *replacement;
+
+	if (!ef)
+		return -EINVAL;
+
+	/* TODO: Instead of block before we should use the fence of the page
+	 * table update and TLB flush here directly.
+	 */
+	replacement = dma_fence_get_stub();
+	dma_resv_replace_fences(bo->tbo.base.resv, ef->base.context,
+				replacement, DMA_RESV_USAGE_BOOKKEEP);
+	dma_fence_put(replacement);
+	return 0;
+}
+
+int amdgpu_amdkfd_remove_fence_on_pt_pd_bos(struct amdgpu_bo *bo)
+{
+	struct amdgpu_bo *root = bo;
+	struct amdgpu_vm_bo_base *vm_bo;
+	struct amdgpu_vm *vm;
+	struct amdkfd_process_info *info;
+	struct amdgpu_amdkfd_fence *ef;
+	int ret;
+
+	/* we can always get vm_bo from root PD bo.*/
+	while (root->parent)
+		root = root->parent;
+
+	vm_bo = root->vm_bo;
+	if (!vm_bo)
+		return 0;
+
+	vm = vm_bo->vm;
+	if (!vm)
+		return 0;
+
+	info = vm->process_info;
+	if (!info || !info->eviction_fence)
+		return 0;
+
+	ef = container_of(dma_fence_get(&info->eviction_fence->base),
+			struct amdgpu_amdkfd_fence, base);
+
+	BUG_ON(!dma_resv_trylock(bo->tbo.base.resv));
+	ret = amdgpu_amdkfd_remove_eviction_fence(bo, ef);
+	dma_resv_unlock(bo->tbo.base.resv);
+
+	dma_fence_put(&ef->base);
+	return ret;
+}
+
+static int amdgpu_amdkfd_bo_validate(struct amdgpu_bo *bo, uint32_t domain,
+				     bool wait)
+{
+	struct ttm_operation_ctx ctx = { false, false };
+	int ret;
+
+	if (WARN(amdgpu_ttm_tt_get_usermm(bo->tbo.ttm),
+		 "Called with userptr BO"))
+		return -EINVAL;
+
+	amdgpu_bo_placement_from_domain(bo, domain);
+
+	ret = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
+	if (ret)
+		goto validate_fail;
+	if (wait)
+		amdgpu_bo_sync_wait(bo, AMDGPU_FENCE_OWNER_KFD, false);
+
+validate_fail:
+	return ret;
+}
+
+static int amdgpu_amdkfd_validate_vm_bo(void *_unused, struct amdgpu_bo *bo)
+{
+	return amdgpu_amdkfd_bo_validate(bo, bo->allowed_domains, false);
+}
+
+/* vm_validate_pt_pd_bos - Validate page table and directory BOs
+ *
+ * Page directories are not updated here because huge page handling
+ * during page table updates can invalidate page directory entries
+ * again. Page directories are only updated after updating page
+ * tables.
+ */
+static int vm_validate_pt_pd_bos(struct amdgpu_vm *vm)
+{
+	struct amdgpu_bo *pd = vm->root.bo;
+	struct amdgpu_device *adev = amdgpu_ttm_adev(pd->tbo.bdev);
+	int ret;
+
+	ret = amdgpu_vm_validate_pt_bos(adev, vm, amdgpu_amdkfd_validate_vm_bo, NULL);
+	if (ret) {
+		pr_err("failed to validate PT BOs\n");
+		return ret;
+	}
+
+	vm->pd_phys_addr = amdgpu_gmc_pd_addr(vm->root.bo);
+
+	return 0;
+}
+
+static int vm_update_pds(struct amdgpu_vm *vm, struct amdgpu_sync *sync)
+{
+	struct amdgpu_bo *pd = vm->root.bo;
+	struct amdgpu_device *adev = amdgpu_ttm_adev(pd->tbo.bdev);
+	int ret;
+
+	ret = amdgpu_vm_update_pdes(adev, vm, false);
+	if (ret)
+		return ret;
+
+	return amdgpu_sync_fence(sync, vm->last_update);
+}
+
+static uint64_t get_pte_flags(struct amdgpu_device *adev, struct kgd_mem *mem)
+{
+	struct amdgpu_device *bo_adev = amdgpu_ttm_adev(mem->bo->tbo.bdev);
+	bool coherent = mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_COHERENT;
+	bool uncached = mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_UNCACHED;
+	uint32_t mapping_flags;
+	uint64_t pte_flags;
+	bool snoop = false;
+
+	mapping_flags = AMDGPU_VM_PAGE_READABLE;
+	if (mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_WRITABLE)
+		mapping_flags |= AMDGPU_VM_PAGE_WRITEABLE;
+	if (mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_EXECUTABLE)
+		mapping_flags |= AMDGPU_VM_PAGE_EXECUTABLE;
+
+	switch (adev->asic_type) {
+	case CHIP_ARCTURUS:
+	case CHIP_ALDEBARAN:
+		if (mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_VRAM) {
+			if (bo_adev == adev) {
+				if (uncached)
+					mapping_flags |= AMDGPU_VM_MTYPE_UC;
+				else if (coherent)
+					mapping_flags |= AMDGPU_VM_MTYPE_CC;
+				else
+					mapping_flags |= AMDGPU_VM_MTYPE_RW;
+				if (adev->asic_type == CHIP_ALDEBARAN &&
+				    adev->gmc.xgmi.connected_to_cpu)
+					snoop = true;
+			} else {
+				if (uncached || coherent)
+					mapping_flags |= AMDGPU_VM_MTYPE_UC;
+				else
+					mapping_flags |= AMDGPU_VM_MTYPE_NC;
+				if (amdgpu_xgmi_same_hive(adev, bo_adev))
+					snoop = true;
+			}
+		} else {
+			if (uncached || coherent)
+				mapping_flags |= AMDGPU_VM_MTYPE_UC;
+			else
+				mapping_flags |= AMDGPU_VM_MTYPE_NC;
+			snoop = true;
+		}
+		break;
+	default:
+		if (uncached || coherent)
+			mapping_flags |= AMDGPU_VM_MTYPE_UC;
+		else
+			mapping_flags |= AMDGPU_VM_MTYPE_NC;
+
+		if (!(mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_VRAM))
+			snoop = true;
+	}
+
+	pte_flags = amdgpu_gem_va_map_flags(adev, mapping_flags);
+	pte_flags |= snoop ? AMDGPU_PTE_SNOOPED : 0;
+
+	return pte_flags;
+}
+
+/**
+ * create_sg_table() - Create an sg_table for a contiguous DMA addr range
+ * @addr: The starting address to point to
+ * @size: Size of memory area in bytes being pointed to
+ *
+ * Allocates an instance of sg_table and initializes it to point to memory
+ * area specified by input parameters. The address used to build is assumed
+ * to be DMA mapped, if needed.
+ *
+ * DOORBELL or MMIO BOs use only one scatterlist node in their sg_table
+ * because they are physically contiguous.
+ *
+ * Return: Initialized instance of SG Table or NULL
+ */
+static struct sg_table *create_sg_table(uint64_t addr, uint32_t size)
+{
+	struct sg_table *sg = kmalloc(sizeof(*sg), GFP_KERNEL);
+
+	if (!sg)
+		return NULL;
+	if (sg_alloc_table(sg, 1, GFP_KERNEL)) {
+		kfree(sg);
+		return NULL;
+	}
+	sg_dma_address(sg->sgl) = addr;
+	sg->sgl->length = size;
+#ifdef CONFIG_NEED_SG_DMA_LENGTH
+	sg->sgl->dma_length = size;
+#endif
+	return sg;
+}
+
+static int
+kfd_mem_dmamap_userptr(struct kgd_mem *mem,
+		       struct kfd_mem_attachment *attachment)
+{
+	enum dma_data_direction direction =
+		mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_WRITABLE ?
+		DMA_BIDIRECTIONAL : DMA_TO_DEVICE;
+	struct ttm_operation_ctx ctx = {.interruptible = true};
+	struct amdgpu_bo *bo = attachment->bo_va->base.bo;
+	struct amdgpu_device *adev = attachment->adev;
+	struct ttm_tt *src_ttm = mem->bo->tbo.ttm;
+	struct ttm_tt *ttm = bo->tbo.ttm;
+	int ret;
+
+	if (WARN_ON(ttm->num_pages != src_ttm->num_pages))
+		return -EINVAL;
+
+	ttm->sg = kmalloc(sizeof(*ttm->sg), GFP_KERNEL);
+	if (unlikely(!ttm->sg))
+		return -ENOMEM;
+
+	/* Same sequence as in amdgpu_ttm_tt_pin_userptr */
+	ret = sg_alloc_table_from_pages(ttm->sg, src_ttm->pages,
+					ttm->num_pages, 0,
+					(u64)ttm->num_pages << PAGE_SHIFT,
+					GFP_KERNEL);
+	if (unlikely(ret))
+		goto free_sg;
+
+	ret = dma_map_sgtable(adev->dev, ttm->sg, direction, 0);
+	if (unlikely(ret))
+		goto release_sg;
+
+	drm_prime_sg_to_dma_addr_array(ttm->sg, ttm->dma_address,
+				       ttm->num_pages);
+
+	amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_GTT);
+	ret = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
+	if (ret)
+		goto unmap_sg;
+
+	return 0;
+
+unmap_sg:
+	dma_unmap_sgtable(adev->dev, ttm->sg, direction, 0);
+release_sg:
+	pr_err("DMA map userptr failed: %d\n", ret);
+	sg_free_table(ttm->sg);
+free_sg:
+	kfree(ttm->sg);
+	ttm->sg = NULL;
+	return ret;
+}
+
+static int
+kfd_mem_dmamap_dmabuf(struct kfd_mem_attachment *attachment)
+{
+	struct ttm_operation_ctx ctx = {.interruptible = true};
+	struct amdgpu_bo *bo = attachment->bo_va->base.bo;
+
+	amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_GTT);
+	return ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
+}
+
+/**
+ * kfd_mem_dmamap_sg_bo() - Create DMA mapped sg_table to access DOORBELL or MMIO BO
+ * @mem: SG BO of the DOORBELL or MMIO resource on the owning device
+ * @attachment: Virtual address attachment of the BO on accessing device
+ *
+ * An access request from the device that owns DOORBELL does not require DMA mapping.
+ * This is because the request doesn't go through PCIe root complex i.e. it instead
+ * loops back. The need to DMA map arises only when accessing peer device's DOORBELL
+ *
+ * In contrast, all access requests for MMIO need to be DMA mapped without regard to
+ * device ownership. This is because access requests for MMIO go through PCIe root
+ * complex.
+ *
+ * This is accomplished in two steps:
+ *   - Obtain DMA mapped address of DOORBELL or MMIO memory that could be used
+ *         in updating requesting device's page table
+ *   - Signal TTM to mark memory pointed to by requesting device's BO as GPU
+ *         accessible. This allows an update of requesting device's page table
+ *         with entries associated with DOOREBELL or MMIO memory
+ *
+ * This method is invoked in the following contexts:
+ *   - Mapping of DOORBELL or MMIO BO of same or peer device
+ *   - Validating an evicted DOOREBELL or MMIO BO on device seeking access
+ *
+ * Return: ZERO if successful, NON-ZERO otherwise
+ */
+static int
+kfd_mem_dmamap_sg_bo(struct kgd_mem *mem,
+		     struct kfd_mem_attachment *attachment)
+{
+	struct ttm_operation_ctx ctx = {.interruptible = true};
+	struct amdgpu_bo *bo = attachment->bo_va->base.bo;
+	struct amdgpu_device *adev = attachment->adev;
+	struct ttm_tt *ttm = bo->tbo.ttm;
+	enum dma_data_direction dir;
+	dma_addr_t dma_addr;
+	bool mmio;
+	int ret;
+
+	/* Expect SG Table of dmapmap BO to be NULL */
+	mmio = (mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_MMIO_REMAP);
+	if (unlikely(ttm->sg)) {
+		pr_err("SG Table of %d BO for peer device is UNEXPECTEDLY NON-NULL", mmio);
+		return -EINVAL;
+	}
+
+	dir = mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_WRITABLE ?
+			DMA_BIDIRECTIONAL : DMA_TO_DEVICE;
+	dma_addr = mem->bo->tbo.sg->sgl->dma_address;
+	pr_debug("%d BO size: %d\n", mmio, mem->bo->tbo.sg->sgl->length);
+	pr_debug("%d BO address before DMA mapping: %llx\n", mmio, dma_addr);
+	dma_addr = dma_map_resource(adev->dev, dma_addr,
+			mem->bo->tbo.sg->sgl->length, dir, DMA_ATTR_SKIP_CPU_SYNC);
+	ret = dma_mapping_error(adev->dev, dma_addr);
+	if (unlikely(ret))
+		return ret;
+	pr_debug("%d BO address after DMA mapping: %llx\n", mmio, dma_addr);
+
+	ttm->sg = create_sg_table(dma_addr, mem->bo->tbo.sg->sgl->length);
+	if (unlikely(!ttm->sg)) {
+		ret = -ENOMEM;
+		goto unmap_sg;
+	}
+
+	amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_GTT);
+	ret = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
+	if (unlikely(ret))
+		goto free_sg;
+
+	return ret;
+
+free_sg:
+	sg_free_table(ttm->sg);
+	kfree(ttm->sg);
+	ttm->sg = NULL;
+unmap_sg:
+	dma_unmap_resource(adev->dev, dma_addr, mem->bo->tbo.sg->sgl->length,
+			   dir, DMA_ATTR_SKIP_CPU_SYNC);
+	return ret;
+}
+
+static int
+kfd_mem_dmamap_attachment(struct kgd_mem *mem,
+			  struct kfd_mem_attachment *attachment)
+{
+	switch (attachment->type) {
+	case KFD_MEM_ATT_SHARED:
+		return 0;
+	case KFD_MEM_ATT_USERPTR:
+		return kfd_mem_dmamap_userptr(mem, attachment);
+	case KFD_MEM_ATT_DMABUF:
+		return kfd_mem_dmamap_dmabuf(attachment);
+	case KFD_MEM_ATT_SG:
+		return kfd_mem_dmamap_sg_bo(mem, attachment);
+	default:
+		WARN_ON_ONCE(1);
+	}
+	return -EINVAL;
+}
+
+static void
+kfd_mem_dmaunmap_userptr(struct kgd_mem *mem,
+			 struct kfd_mem_attachment *attachment)
+{
+	enum dma_data_direction direction =
+		mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_WRITABLE ?
+		DMA_BIDIRECTIONAL : DMA_TO_DEVICE;
+	struct ttm_operation_ctx ctx = {.interruptible = false};
+	struct amdgpu_bo *bo = attachment->bo_va->base.bo;
+	struct amdgpu_device *adev = attachment->adev;
+	struct ttm_tt *ttm = bo->tbo.ttm;
+
+	if (unlikely(!ttm->sg))
+		return;
+
+	amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_CPU);
+	ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
+
+	dma_unmap_sgtable(adev->dev, ttm->sg, direction, 0);
+	sg_free_table(ttm->sg);
+	kfree(ttm->sg);
+	ttm->sg = NULL;
+}
+
+static void
+kfd_mem_dmaunmap_dmabuf(struct kfd_mem_attachment *attachment)
+{
+	struct ttm_operation_ctx ctx = {.interruptible = true};
+	struct amdgpu_bo *bo = attachment->bo_va->base.bo;
+
+	amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_CPU);
+	ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
+}
+
+/**
+ * kfd_mem_dmaunmap_sg_bo() - Free DMA mapped sg_table of DOORBELL or MMIO BO
+ * @mem: SG BO of the DOORBELL or MMIO resource on the owning device
+ * @attachment: Virtual address attachment of the BO on accessing device
+ *
+ * The method performs following steps:
+ *   - Signal TTM to mark memory pointed to by BO as GPU inaccessible
+ *   - Free SG Table that is used to encapsulate DMA mapped memory of
+ *          peer device's DOORBELL or MMIO memory
+ *
+ * This method is invoked in the following contexts:
+ *     UNMapping of DOORBELL or MMIO BO on a device having access to its memory
+ *     Eviction of DOOREBELL or MMIO BO on device having access to its memory
+ *
+ * Return: void
+ */
+static void
+kfd_mem_dmaunmap_sg_bo(struct kgd_mem *mem,
+		       struct kfd_mem_attachment *attachment)
+{
+	struct ttm_operation_ctx ctx = {.interruptible = true};
+	struct amdgpu_bo *bo = attachment->bo_va->base.bo;
+	struct amdgpu_device *adev = attachment->adev;
+	struct ttm_tt *ttm = bo->tbo.ttm;
+	enum dma_data_direction dir;
+
+	if (unlikely(!ttm->sg)) {
+		pr_err("SG Table of BO is UNEXPECTEDLY NULL");
+		return;
+	}
+
+	amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_CPU);
+	ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
+
+	dir = mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_WRITABLE ?
+				DMA_BIDIRECTIONAL : DMA_TO_DEVICE;
+	dma_unmap_resource(adev->dev, ttm->sg->sgl->dma_address,
+			ttm->sg->sgl->length, dir, DMA_ATTR_SKIP_CPU_SYNC);
+	sg_free_table(ttm->sg);
+	kfree(ttm->sg);
+	ttm->sg = NULL;
+	bo->tbo.sg = NULL;
+}
+
+static void
+kfd_mem_dmaunmap_attachment(struct kgd_mem *mem,
+			    struct kfd_mem_attachment *attachment)
+{
+	switch (attachment->type) {
+	case KFD_MEM_ATT_SHARED:
+		break;
+	case KFD_MEM_ATT_USERPTR:
+		kfd_mem_dmaunmap_userptr(mem, attachment);
+		break;
+	case KFD_MEM_ATT_DMABUF:
+		kfd_mem_dmaunmap_dmabuf(attachment);
+		break;
+	case KFD_MEM_ATT_SG:
+		kfd_mem_dmaunmap_sg_bo(mem, attachment);
+		break;
+	default:
+		WARN_ON_ONCE(1);
+	}
+}
+
+static int
+kfd_mem_attach_dmabuf(struct amdgpu_device *adev, struct kgd_mem *mem,
+		      struct amdgpu_bo **bo)
+{
+	struct drm_gem_object *gobj;
+	int ret;
+
+	if (!mem->dmabuf) {
+		mem->dmabuf = amdgpu_gem_prime_export(&mem->bo->tbo.base,
+			mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_WRITABLE ?
+				DRM_RDWR : 0);
+		if (IS_ERR(mem->dmabuf)) {
+			ret = PTR_ERR(mem->dmabuf);
+			mem->dmabuf = NULL;
+			return ret;
+		}
+	}
+
+	gobj = amdgpu_gem_prime_import(adev_to_drm(adev), mem->dmabuf);
+	if (IS_ERR(gobj))
+		return PTR_ERR(gobj);
+
+	*bo = gem_to_amdgpu_bo(gobj);
+	(*bo)->flags |= AMDGPU_GEM_CREATE_PREEMPTIBLE;
+
+	return 0;
+}
+
+/* kfd_mem_attach - Add a BO to a VM
+ *
+ * Everything that needs to bo done only once when a BO is first added
+ * to a VM. It can later be mapped and unmapped many times without
+ * repeating these steps.
+ *
+ * 0. Create BO for DMA mapping, if needed
+ * 1. Allocate and initialize BO VA entry data structure
+ * 2. Add BO to the VM
+ * 3. Determine ASIC-specific PTE flags
+ * 4. Alloc page tables and directories if needed
+ * 4a.  Validate new page tables and directories
+ */
+static int kfd_mem_attach(struct amdgpu_device *adev, struct kgd_mem *mem,
+		struct amdgpu_vm *vm, bool is_aql)
+{
+	struct amdgpu_device *bo_adev = amdgpu_ttm_adev(mem->bo->tbo.bdev);
+	unsigned long bo_size = mem->bo->tbo.base.size;
+	uint64_t va = mem->va;
+	struct kfd_mem_attachment *attachment[2] = {NULL, NULL};
+	struct amdgpu_bo *bo[2] = {NULL, NULL};
+	bool same_hive = false;
+	int i, ret;
+
+	if (!va) {
+		pr_err("Invalid VA when adding BO to VM\n");
+		return -EINVAL;
+	}
+
+	/* Determine access to VRAM, MMIO and DOORBELL BOs of peer devices
+	 *
+	 * The access path of MMIO and DOORBELL BOs of is always over PCIe.
+	 * In contrast the access path of VRAM BOs depens upon the type of
+	 * link that connects the peer device. Access over PCIe is allowed
+	 * if peer device has large BAR. In contrast, access over xGMI is
+	 * allowed for both small and large BAR configurations of peer device
+	 */
+	if ((adev != bo_adev) &&
+	    ((mem->domain == AMDGPU_GEM_DOMAIN_VRAM) ||
+	     (mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_DOORBELL) ||
+	     (mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_MMIO_REMAP))) {
+		if (mem->domain == AMDGPU_GEM_DOMAIN_VRAM)
+			same_hive = amdgpu_xgmi_same_hive(adev, bo_adev);
+		if (!same_hive && !amdgpu_device_is_peer_accessible(bo_adev, adev))
+			return -EINVAL;
+	}
+
+	for (i = 0; i <= is_aql; i++) {
+		attachment[i] = kzalloc(sizeof(*attachment[i]), GFP_KERNEL);
+		if (unlikely(!attachment[i])) {
+			ret = -ENOMEM;
+			goto unwind;
+		}
+
+		pr_debug("\t add VA 0x%llx - 0x%llx to vm %p\n", va,
+			 va + bo_size, vm);
+
+		if ((adev == bo_adev && !(mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_MMIO_REMAP)) ||
+		    (amdgpu_ttm_tt_get_usermm(mem->bo->tbo.ttm) && adev->ram_is_direct_mapped) ||
+		    same_hive) {
+			/* Mappings on the local GPU, or VRAM mappings in the
+			 * local hive, or userptr mapping IOMMU direct map mode
+			 * share the original BO
+			 */
+			attachment[i]->type = KFD_MEM_ATT_SHARED;
+			bo[i] = mem->bo;
+			drm_gem_object_get(&bo[i]->tbo.base);
+		} else if (i > 0) {
+			/* Multiple mappings on the same GPU share the BO */
+			attachment[i]->type = KFD_MEM_ATT_SHARED;
+			bo[i] = bo[0];
+			drm_gem_object_get(&bo[i]->tbo.base);
+		} else if (amdgpu_ttm_tt_get_usermm(mem->bo->tbo.ttm)) {
+			/* Create an SG BO to DMA-map userptrs on other GPUs */
+			attachment[i]->type = KFD_MEM_ATT_USERPTR;
+			ret = create_dmamap_sg_bo(adev, mem, &bo[i]);
+			if (ret)
+				goto unwind;
+		/* Handle DOORBELL BOs of peer devices and MMIO BOs of local and peer devices */
+		} else if (mem->bo->tbo.type == ttm_bo_type_sg) {
+			WARN_ONCE(!(mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_DOORBELL ||
+				    mem->alloc_flags & KFD_IOC_ALLOC_MEM_FLAGS_MMIO_REMAP),
+				  "Handing invalid SG BO in ATTACH request");
+			attachment[i]->type = KFD_MEM_ATT_SG;
+			ret = create_dmamap_sg_bo(adev, mem, &bo[i]);
+			if (ret)
+				goto unwind;
+		/* Enable acces to GTT and VRAM BOs of peer devices */
+		} else if (mem->domain == AMDGPU_GEM_DOMAIN_GTT ||
+			   mem->domain == AMDGPU_GEM_DOMAIN_VRAM) {
+			attachment[i]->type = KFD_MEM_ATT_DMABUF;
+			ret = kfd_mem_attach_dmabuf(adev, mem, &bo[i]);
+			if (ret)
+				goto unwind;
+			pr_debug("Employ DMABUF mechanism to enable peer GPU access\n");
+		} else {
+			WARN_ONCE(true, "Handling invalid ATTACH request");
+			ret = -EINVAL;
+			goto unwind;
+		}
+
+		/* Add BO to VM internal data structures */
+		ret = amdgpu_bo_reserve(bo[i], false);
+		if (ret) {
+			pr_debug("Unable to reserve BO during memory attach");
+			goto unwind;
+		}
+		attachment[i]->bo_va = amdgpu_vm_bo_add(adev, vm, bo[i]);
+		amdgpu_bo_unreserve(bo[i]);
+		if (unlikely(!attachment[i]->bo_va)) {
+			ret = -ENOMEM;
+			pr_err("Failed to add BO object to VM. ret == %d\n",
+			       ret);
+			goto unwind;
+		}
+		attachment[i]->va = va;
+		attachment[i]->pte_flags = get_pte_flags(adev, mem);
+		attachment[i]->adev = adev;
+		list_add(&attachment[i]->list, &mem->attachments);
+
+		va += bo_size;
+	}
+
+	return 0;
+
+unwind:
+	for (; i >= 0; i--) {
+		if (!attachment[i])
+			continue;
+		if (attachment[i]->bo_va) {
+			amdgpu_bo_reserve(bo[i], true);
+			amdgpu_vm_bo_del(adev, attachment[i]->bo_va);
+			amdgpu_bo_unreserve(bo[i]);
+			list_del(&attachment[i]->list);
+		}
+		if (bo[i])
+			drm_gem_object_put(&bo[i]->tbo.base);
+		kfree(attachment[i]);
+	}
+	return ret;
+}
+
+static void kfd_mem_detach(struct kfd_mem_attachment *attachment)
+{
+	struct amdgpu_bo *bo = attachment->bo_va->base.bo;
+
+	pr_debug("\t remove VA 0x%llx in entry %p\n",
+			attachment->va, attachment);
+	amdgpu_vm_bo_del(attachment->adev, attachment->bo_va);
+	drm_gem_object_put(&bo->tbo.base);
+	list_del(&attachment->list);
+	kfree(attachment);
+}
+
+static void add_kgd_mem_to_kfd_bo_list(struct kgd_mem *mem,
+				struct amdkfd_process_info *process_info,
+				bool userptr)
+{
+	struct ttm_validate_buffer *entry = &mem->validate_list;
+	struct amdgpu_bo *bo = mem->bo;
+
+	INIT_LIST_HEAD(&entry->head);
+	entry->num_shared = 1;
+	entry->bo = &bo->tbo;
+	mutex_lock(&process_info->lock);
+	if (userptr)
+		list_add_tail(&entry->head, &process_info->userptr_valid_list);
+	else
+		list_add_tail(&entry->head, &process_info->kfd_bo_list);
+	mutex_unlock(&process_info->lock);
+}
+
+static void remove_kgd_mem_from_kfd_bo_list(struct kgd_mem *mem,
+		struct amdkfd_process_info *process_info)
+{
+	struct ttm_validate_buffer *bo_list_entry;
+
+	bo_list_entry = &mem->validate_list;
+	mutex_lock(&process_info->lock);
+	list_del(&bo_list_entry->head);
+	mutex_unlock(&process_info->lock);
+}
+
+/* Initializes user pages. It registers the MMU notifier and validates
+ * the userptr BO in the GTT domain.
+ *
+ * The BO must already be on the userptr_valid_list. Otherwise an
+ * eviction and restore may happen that leaves the new BO unmapped
+ * with the user mode queues running.
+ *
+ * Takes the process_info->lock to protect against concurrent restore
+ * workers.
+ *
+ * Returns 0 for success, negative errno for errors.
+ */
+static int init_user_pages(struct kgd_mem *mem, uint64_t user_addr,
+			   bool criu_resume)
+{
+	struct amdkfd_process_info *process_info = mem->process_info;
+	struct amdgpu_bo *bo = mem->bo;
+	struct ttm_operation_ctx ctx = { true, false };
+	struct hmm_range *range;
+	int ret = 0;
+
+	mutex_lock(&process_info->lock);
+
+	ret = amdgpu_ttm_tt_set_userptr(&bo->tbo, user_addr, 0);
+	if (ret) {
+		pr_err("%s: Failed to set userptr: %d\n", __func__, ret);
+		goto out;
+	}
+
+	ret = amdgpu_mn_register(bo, user_addr);
+	if (ret) {
+		pr_err("%s: Failed to register MMU notifier: %d\n",
+		       __func__, ret);
+		goto out;
+	}
+
+	if (criu_resume) {
+		/*
+		 * During a CRIU restore operation, the userptr buffer objects
+		 * will be validated in the restore_userptr_work worker at a
+		 * later stage when it is scheduled by another ioctl called by
+		 * CRIU master process for the target pid for restore.
+		 */
+		atomic_inc(&mem->invalid);
+		mutex_unlock(&process_info->lock);
+		return 0;
+	}
+
+	ret = amdgpu_ttm_tt_get_user_pages(bo, bo->tbo.ttm->pages, &range);
+	if (ret) {
+		pr_err("%s: Failed to get user pages: %d\n", __func__, ret);
+		goto unregister_out;
+	}
+
+	ret = amdgpu_bo_reserve(bo, true);
+	if (ret) {
+		pr_err("%s: Failed to reserve BO\n", __func__);
+		goto release_out;
+	}
+	amdgpu_bo_placement_from_domain(bo, mem->domain);
+	ret = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
+	if (ret)
+		pr_err("%s: failed to validate BO\n", __func__);
+	amdgpu_bo_unreserve(bo);
+
+release_out:
+	amdgpu_ttm_tt_get_user_pages_done(bo->tbo.ttm, range);
+unregister_out:
+	if (ret)
+		amdgpu_mn_unregister(bo);
+out:
+	mutex_unlock(&process_info->lock);
+	return ret;
+}
+
+/* Reserving a BO and its page table BOs must happen atomically to
+ * avoid deadlocks. Some operations update multiple VMs at once. Track
+ * all the reservation info in a context structure. Optionally a sync
+ * object can track VM updates.
+ */
+struct bo_vm_reservation_context {
+	struct amdgpu_bo_list_entry kfd_bo; /* BO list entry for the KFD BO */
+	unsigned int n_vms;		    /* Number of VMs reserved	    */
+	struct amdgpu_bo_list_entry *vm_pd; /* Array of VM BO list entries  */
+	struct ww_acquire_ctx ticket;	    /* Reservation ticket	    */
+	struct list_head list, duplicates;  /* BO lists			    */
+	struct amdgpu_sync *sync;	    /* Pointer to sync object	    */
+	bool reserved;			    /* Whether BOs are reserved	    */
+};
+
+enum bo_vm_match {
+	BO_VM_NOT_MAPPED = 0,	/* Match VMs where a BO is not mapped */
+	BO_VM_MAPPED,		/* Match VMs where a BO is mapped     */
+	BO_VM_ALL,		/* Match all VMs a BO was added to    */
+};
+
+/**
+ * reserve_bo_and_vm - reserve a BO and a VM unconditionally.
+ * @mem: KFD BO structure.
+ * @vm: the VM to reserve.
+ * @ctx: the struct that will be used in unreserve_bo_and_vms().
+ */
+static int reserve_bo_and_vm(struct kgd_mem *mem,
+			      struct amdgpu_vm *vm,
+			      struct bo_vm_reservation_context *ctx)
+{
+	struct amdgpu_bo *bo = mem->bo;
+	int ret;
+
+	WARN_ON(!vm);
+
+	ctx->reserved = false;
+	ctx->n_vms = 1;
+	ctx->sync = &mem->sync;
+
+	INIT_LIST_HEAD(&ctx->list);
+	INIT_LIST_HEAD(&ctx->duplicates);
+
+	ctx->vm_pd = kcalloc(ctx->n_vms, sizeof(*ctx->vm_pd), GFP_KERNEL);
+	if (!ctx->vm_pd)
+		return -ENOMEM;
+
+	ctx->kfd_bo.priority = 0;
+	ctx->kfd_bo.tv.bo = &bo->tbo;
+	ctx->kfd_bo.tv.num_shared = 1;
+	list_add(&ctx->kfd_bo.tv.head, &ctx->list);
+
+	amdgpu_vm_get_pd_bo(vm, &ctx->list, &ctx->vm_pd[0]);
+
+	ret = ttm_eu_reserve_buffers(&ctx->ticket, &ctx->list,
+				     false, &ctx->duplicates);
+	if (ret) {
+		pr_err("Failed to reserve buffers in ttm.\n");
+		kfree(ctx->vm_pd);
+		ctx->vm_pd = NULL;
+		return ret;
+	}
+
+	ctx->reserved = true;
+	return 0;
+}
+
+/**
+ * reserve_bo_and_cond_vms - reserve a BO and some VMs conditionally
+ * @mem: KFD BO structure.
+ * @vm: the VM to reserve. If NULL, then all VMs associated with the BO
+ * is used. Otherwise, a single VM associated with the BO.
+ * @map_type: the mapping status that will be used to filter the VMs.
+ * @ctx: the struct that will be used in unreserve_bo_and_vms().
+ *
+ * Returns 0 for success, negative for failure.
+ */
+static int reserve_bo_and_cond_vms(struct kgd_mem *mem,
+				struct amdgpu_vm *vm, enum bo_vm_match map_type,
+				struct bo_vm_reservation_context *ctx)
+{
+	struct amdgpu_bo *bo = mem->bo;
+	struct kfd_mem_attachment *entry;
+	unsigned int i;
+	int ret;
+
+	ctx->reserved = false;
+	ctx->n_vms = 0;
+	ctx->vm_pd = NULL;
+	ctx->sync = &mem->sync;
+
+	INIT_LIST_HEAD(&ctx->list);
+	INIT_LIST_HEAD(&ctx->duplicates);
+
+	list_for_each_entry(entry, &mem->attachments, list) {
+		if ((vm && vm != entry->bo_va->base.vm) ||
+			(entry->is_mapped != map_type
+			&& map_type != BO_VM_ALL))
+			continue;
+
+		ctx->n_vms++;
+	}
+
+	if (ctx->n_vms != 0) {
+		ctx->vm_pd = kcalloc(ctx->n_vms, sizeof(*ctx->vm_pd),
+				     GFP_KERNEL);
+		if (!ctx->vm_pd)
+			return -ENOMEM;
+	}
+
+	ctx->kfd_bo.priority = 0;
+	ctx->kfd_bo.tv.bo = &bo->tbo;
+	ctx->kfd_bo.tv.num_shared = 1;
+	list_add(&ctx->kfd_bo.tv.head, &ctx->list);
+
+	i = 0;
+	list_for_each_entry(entry, &mem->attachments, list) {
+		if ((vm && vm != entry->bo_va->base.vm) ||
+			(entry->is_mapped != map_type
+			&& map_type != BO_VM_ALL))
+			continue;
+
+		amdgpu_vm_get_pd_bo(entry->bo_va->base.vm, &ctx->list,
+				&ctx->vm_pd[i]);
+		i++;
+	}
+
+	ret = ttm_eu_reserve_buffers(&ctx->ticket, &ctx->list,
+				     false, &ctx->duplicates);
+	if (ret) {
+		pr_err("Failed to reserve buffers in ttm.\n");
+		kfree(ctx->vm_pd);
+		ctx->vm_pd = NULL;
+		return ret;
+	}
+
+	ctx->reserved = true;
+	return 0;
+}
+
+/**
+ * unreserve_bo_and_vms - Unreserve BO and VMs from a reservation context
+ * @ctx: Reservation context to unreserve
+ * @wait: Optionally wait for a sync object representing pending VM updates
+ * @intr: Whether the wait is interruptible
+ *
+ * Also frees any resources allocated in
+ * reserve_bo_and_(cond_)vm(s). Returns the status from
+ * amdgpu_sync_wait.
+ */
+static int unreserve_bo_and_vms(struct bo_vm_reservation_context *ctx,
+				 bool wait, bool intr)
+{
+	int ret = 0;
+
+	if (wait)
+		ret = amdgpu_sync_wait(ctx->sync, intr);
+
+	if (ctx->reserved)
+		ttm_eu_backoff_reservation(&ctx->ticket, &ctx->list);
+	kfree(ctx->vm_pd);
+
+	ctx->sync = NULL;
+
+	ctx->reserved = false;
+	ctx->vm_pd = NULL;
+
+	return ret;
+}
+
+static void unmap_bo_from_gpuvm(struct kgd_mem *mem,
+				struct kfd_mem_attachment *entry,
+				struct amdgpu_sync *sync)
+{
+	struct amdgpu_bo_va *bo_va = entry->bo_va;
+	struct amdgpu_device *adev = entry->adev;
+	struct amdgpu_vm *vm = bo_va->base.vm;
+
+	amdgpu_vm_bo_unmap(adev, bo_va, entry->va);
+
+	amdgpu_vm_clear_freed(adev, vm, &bo_va->last_pt_update);
+
+	amdgpu_sync_fence(sync, bo_va->last_pt_update);
+
+	kfd_mem_dmaunmap_attachment(mem, entry);
+}
+
+static int update_gpuvm_pte(struct kgd_mem *mem,
+			    struct kfd_mem_attachment *entry,
+			    struct amdgpu_sync *sync)
+{
+	struct amdgpu_bo_va *bo_va = entry->bo_va;
+	struct amdgpu_device *adev = entry->adev;
+	int ret;
+
+	ret = kfd_mem_dmamap_attachment(mem, entry);
+	if (ret)
+		return ret;
+
+	/* Update the page tables  */
+	ret = amdgpu_vm_bo_update(adev, bo_va, false);
+	if (ret) {
+		pr_err("amdgpu_vm_bo_update failed\n");
+		return ret;
+	}
+
+	return amdgpu_sync_fence(sync, bo_va->last_pt_update);
+}
+
+static int map_bo_to_gpuvm(struct kgd_mem *mem,
+			   struct kfd_mem_attachment *entry,
+			   struct amdgpu_sync *sync,
+			   bool no_update_pte)
+{
+	int ret;
+
+	/* Set virtual address for the allocation */
+	ret = amdgpu_vm_bo_map(entry->adev, entry->bo_va, entry->va, 0,
+			       amdgpu_bo_size(entry->bo_va->base.bo),
+			       entry->pte_flags);
+	if (ret) {
+		pr_err("Failed to map VA 0x%llx in vm. ret %d\n",
+				entry->va, ret);
+		return ret;
+	}
+
+	if (no_update_pte)
+		return 0;
+
+	ret = update_gpuvm_pte(mem, entry, sync);
+	if (ret) {
+		pr_err("update_gpuvm_pte() failed\n");
+		goto update_gpuvm_pte_failed;
+	}
+
+	return 0;
+
+update_gpuvm_pte_failed:
+	unmap_bo_from_gpuvm(mem, entry, sync);
+	return ret;
+}
+
+static int process_validate_vms(struct amdkfd_process_info *process_info)
+{
+	struct amdgpu_vm *peer_vm;
+	int ret;
+
+	list_for_each_entry(peer_vm, &process_info->vm_list_head,
+			    vm_list_node) {
+		ret = vm_validate_pt_pd_bos(peer_vm);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int process_sync_pds_resv(struct amdkfd_process_info *process_info,
+				 struct amdgpu_sync *sync)
+{
+	struct amdgpu_vm *peer_vm;
+	int ret;
+
+	list_for_each_entry(peer_vm, &process_info->vm_list_head,
+			    vm_list_node) {
+		struct amdgpu_bo *pd = peer_vm->root.bo;
+
+		ret = amdgpu_sync_resv(NULL, sync, pd->tbo.base.resv,
+				       AMDGPU_SYNC_NE_OWNER,
+				       AMDGPU_FENCE_OWNER_KFD);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int process_update_pds(struct amdkfd_process_info *process_info,
+			      struct amdgpu_sync *sync)
+{
+	struct amdgpu_vm *peer_vm;
+	int ret;
+
+	list_for_each_entry(peer_vm, &process_info->vm_list_head,
+			    vm_list_node) {
+		ret = vm_update_pds(peer_vm, sync);
+		if (ret)
+			return ret;
+	}
+
+	return 0;
+}
+
+static int init_kfd_vm(struct amdgpu_vm *vm, void **process_info,
+		       struct dma_fence **ef)
+{
+	struct amdkfd_process_info *info = NULL;
+	int ret;
+
+	if (!*process_info) {
+		info = kzalloc(sizeof(*info), GFP_KERNEL);
+		if (!info)
+			return -ENOMEM;
+
+		mutex_init(&info->lock);
+		INIT_LIST_HEAD(&info->vm_list_head);
+		INIT_LIST_HEAD(&info->kfd_bo_list);
+		INIT_LIST_HEAD(&info->userptr_valid_list);
+		INIT_LIST_HEAD(&info->userptr_inval_list);
+
+		info->eviction_fence =
+			amdgpu_amdkfd_fence_create(dma_fence_context_alloc(1),
+						   current->mm,
+						   NULL);
+		if (!info->eviction_fence) {
+			pr_err("Failed to create eviction fence\n");
+			ret = -ENOMEM;
+			goto create_evict_fence_fail;
+		}
+
+		info->pid = get_task_pid(current->group_leader, PIDTYPE_PID);
+		atomic_set(&info->evicted_bos, 0);
+		INIT_DELAYED_WORK(&info->restore_userptr_work,
+				  amdgpu_amdkfd_restore_userptr_worker);
+
+		*process_info = info;
+		*ef = dma_fence_get(&info->eviction_fence->base);
+	}
+
+	vm->process_info = *process_info;
+
+	/* Validate page directory and attach eviction fence */
+	ret = amdgpu_bo_reserve(vm->root.bo, true);
+	if (ret)
+		goto reserve_pd_fail;
+	ret = vm_validate_pt_pd_bos(vm);
+	if (ret) {
+		pr_err("validate_pt_pd_bos() failed\n");
+		goto validate_pd_fail;
+	}
+	ret = amdgpu_bo_sync_wait(vm->root.bo,
+				  AMDGPU_FENCE_OWNER_KFD, false);
+	if (ret)
+		goto wait_pd_fail;
+	ret = dma_resv_reserve_fences(vm->root.bo->tbo.base.resv, 1);
+	if (ret)
+		goto reserve_shared_fail;
+	dma_resv_add_fence(vm->root.bo->tbo.base.resv,
+			   &vm->process_info->eviction_fence->base,
+			   DMA_RESV_USAGE_BOOKKEEP);
+	amdgpu_bo_unreserve(vm->root.bo);
+
+	/* Update process info */
+	mutex_lock(&vm->process_info->lock);
+	list_add_tail(&vm->vm_list_node,
+			&(vm->process_info->vm_list_head));
+	vm->process_info->n_vms++;
+	mutex_unlock(&vm->process_info->lock);
+
+	return 0;
+
+reserve_shared_fail:
+wait_pd_fail:
+validate_pd_fail:
+	amdgpu_bo_unreserve(vm->root.bo);
+reserve_pd_fail:
+	vm->process_info = NULL;
+	if (info) {
+		/* Two fence references: one in info and one in *ef */
+		dma_fence_put(&info->eviction_fence->base);
+		dma_fence_put(*ef);
+		*ef = NULL;
+		*process_info = NULL;
+		put_pid(info->pid);
+create_evict_fence_fail:
+		mutex_destroy(&info->lock);
+		kfree(info);
+	}
+	return ret;
+}
+
+/**
+ * amdgpu_amdkfd_gpuvm_pin_bo() - Pins a BO using following criteria
+ * @bo: Handle of buffer object being pinned
+ * @domain: Domain into which BO should be pinned
+ *
+ *   - USERPTR BOs are UNPINNABLE and will return error
+ *   - All other BO types (GTT, VRAM, MMIO and DOORBELL) will have their
+ *     PIN count incremented. It is valid to PIN a BO multiple times
+ *
+ * Return: ZERO if successful in pinning, Non-Zero in case of error.
+ */
+static int amdgpu_amdkfd_gpuvm_pin_bo(struct amdgpu_bo *bo, u32 domain)
+{
+	int ret = 0;
+
+	ret = amdgpu_bo_reserve(bo, false);
+	if (unlikely(ret))
+		return ret;
+
+	ret = amdgpu_bo_pin_restricted(bo, domain, 0, 0);
+	if (ret)
+		pr_err("Error in Pinning BO to domain: %d\n", domain);
+
+	amdgpu_bo_sync_wait(bo, AMDGPU_FENCE_OWNER_KFD, false);
+	amdgpu_bo_unreserve(bo);
+
+	return ret;
+}
+
+/**
+ * amdgpu_amdkfd_gpuvm_unpin_bo() - Unpins BO using following criteria
+ * @bo: Handle of buffer object being unpinned
+ *
+ *   - Is a illegal request for USERPTR BOs and is ignored
+ *   - All other BO types (GTT, VRAM, MMIO and DOORBELL) will have their
+ *     PIN count decremented. Calls to UNPIN must balance calls to PIN
+ */
+static void amdgpu_amdkfd_gpuvm_unpin_bo(struct amdgpu_bo *bo)
+{
+	int ret = 0;
+
+	ret = amdgpu_bo_reserve(bo, false);
+	if (unlikely(ret))
+		return;
+
+	amdgpu_bo_unpin(bo);
+	amdgpu_bo_unreserve(bo);
+}
+
+int amdgpu_amdkfd_gpuvm_set_vm_pasid(struct amdgpu_device *adev,
+				     struct file *filp, u32 pasid)
+
+{
+	struct amdgpu_fpriv *drv_priv;
+	struct amdgpu_vm *avm;
+	int ret;
+
+	ret = amdgpu_file_to_fpriv(filp, &drv_priv);
+	if (ret)
+		return ret;
+	avm = &drv_priv->vm;
+
+	/* Free the original amdgpu allocated pasid,
+	 * will be replaced with kfd allocated pasid.
+	 */
+	if (avm->pasid) {
+		amdgpu_pasid_free(avm->pasid);
+		amdgpu_vm_set_pasid(adev, avm, 0);
+	}
+
+	ret = amdgpu_vm_set_pasid(adev, avm, pasid);
+	if (ret)
+		return ret;
+
+	return 0;
+}
+
+int amdgpu_amdkfd_gpuvm_acquire_process_vm(struct amdgpu_device *adev,
+					   struct file *filp,
+					   void **process_info,
+					   struct dma_fence **ef)
+{
+	struct amdgpu_fpriv *drv_priv;
+	struct amdgpu_vm *avm;
+	int ret;
+
+	ret = amdgpu_file_to_fpriv(filp, &drv_priv);
+	if (ret)
+		return ret;
+	avm = &drv_priv->vm;
+
+	/* Already a compute VM? */
+	if (avm->process_info)
+		return -EINVAL;
+
+	/* Convert VM into a compute VM */
+	ret = amdgpu_vm_make_compute(adev, avm);
+	if (ret)
+		return ret;
+
+	/* Initialize KFD part of the VM and process info */
+	ret = init_kfd_vm(avm, process_info, ef);
+	if (ret)
+		return ret;
+
+	amdgpu_vm_set_task_info(avm);
+
+	return 0;
+}
+
+void amdgpu_amdkfd_gpuvm_destroy_cb(struct amdgpu_device *adev,
+				    struct amdgpu_vm *vm)
+{
+	struct amdkfd_process_info *process_info = vm->process_info;
+
+	if (!process_info)
+		return;
+
+	/* Update process info */
+	mutex_lock(&process_info->lock);
+	process_info->n_vms--;
+	list_del(&vm->vm_list_node);
+	mutex_unlock(&process_info->lock);
+
+	vm->process_info = NULL;
+
+	/* Release per-process resources when last compute VM is destroyed */
+	if (!process_info->n_vms) {
+		WARN_ON(!list_empty(&process_info->kfd_bo_list));
+		WARN_ON(!list_empty(&process_info->userptr_valid_list));
+		WARN_ON(!list_empty(&process_info->userptr_inval_list));
+
+		dma_fence_put(&process_info->eviction_fence->base);
+		cancel_delayed_work_sync(&process_info->restore_userptr_work);
+		put_pid(process_info->pid);
+		mutex_destroy(&process_info->lock);
+		kfree(process_info);
+	}
+}
+
+void amdgpu_amdkfd_gpuvm_release_process_vm(struct amdgpu_device *adev,
+					    void *drm_priv)
+{
+	struct amdgpu_vm *avm;
+
+	if (WARN_ON(!adev || !drm_priv))
+		return;
+
+	avm = drm_priv_to_vm(drm_priv);
+
+	pr_debug("Releasing process vm %p\n", avm);
+
+	/* The original pasid of amdgpu vm has already been
+	 * released during making a amdgpu vm to a compute vm
+	 * The current pasid is managed by kfd and will be
+	 * released on kfd process destroy. Set amdgpu pasid
+	 * to 0 to avoid duplicate release.
+	 */
+	amdgpu_vm_release_compute(adev, avm);
+}
+
+uint64_t amdgpu_amdkfd_gpuvm_get_process_page_dir(void *drm_priv)
+{
+	struct amdgpu_vm *avm = drm_priv_to_vm(drm_priv);
+	struct amdgpu_bo *pd = avm->root.bo;
+	struct amdgpu_device *adev = amdgpu_ttm_adev(pd->tbo.bdev);
+
+	if (adev->asic_type < CHIP_VEGA10)
+		return avm->pd_phys_addr >> AMDGPU_GPU_PAGE_SHIFT;
+	return avm->pd_phys_addr;
+}
+
+void amdgpu_amdkfd_block_mmu_notifications(void *p)
+{
+	struct amdkfd_process_info *pinfo = (struct amdkfd_process_info *)p;
+
+	mutex_lock(&pinfo->lock);
+	WRITE_ONCE(pinfo->block_mmu_notifications, true);
+	mutex_unlock(&pinfo->lock);
+}
+
+int amdgpu_amdkfd_criu_resume(void *p)
+{
+	int ret = 0;
+	struct amdkfd_process_info *pinfo = (struct amdkfd_process_info *)p;
+
+	mutex_lock(&pinfo->lock);
+	pr_debug("scheduling work\n");
+	atomic_inc(&pinfo->evicted_bos);
+	if (!READ_ONCE(pinfo->block_mmu_notifications)) {
+		ret = -EINVAL;
+		goto out_unlock;
+	}
+	WRITE_ONCE(pinfo->block_mmu_notifications, false);
+	schedule_delayed_work(&pinfo->restore_userptr_work, 0);
+
+out_unlock:
+	mutex_unlock(&pinfo->lock);
+	return ret;
+}
+
+size_t amdgpu_amdkfd_get_available_memory(struct amdgpu_device *adev)
+{
+	uint64_t reserved_for_pt =
+		ESTIMATE_PT_SIZE(amdgpu_amdkfd_total_mem_size);
+	size_t available;
+
+	spin_lock(&kfd_mem_limit.mem_limit_lock);
+	available = adev->gmc.real_vram_size
+		- adev->kfd.vram_used_aligned
+		- atomic64_read(&adev->vram_pin_size)
+		- reserved_for_pt;
+	spin_unlock(&kfd_mem_limit.mem_limit_lock);
+
+	return ALIGN_DOWN(available, VRAM_AVAILABLITY_ALIGN);
+}
+
+int amdgpu_amdkfd_gpuvm_alloc_memory_of_gpu(
+		struct amdgpu_device *adev, uint64_t va, uint64_t size,
+		void *drm_priv, struct kgd_mem **mem,
+		uint64_t *offset, uint32_t flags, bool criu_resume)
+{
+	struct amdgpu_vm *avm = drm_priv_to_vm(drm_priv);
+	enum ttm_bo_type bo_type = ttm_bo_type_device;
+	struct sg_table *sg = NULL;
+	uint64_t user_addr = 0;
+	struct amdgpu_bo *bo;
+	struct drm_gem_object *gobj = NULL;
+	u32 domain, alloc_domain;
+	uint64_t aligned_size;
+	u64 alloc_flags;
+	int ret;
+
+	/*
+	 * Check on which domain to allocate BO
+	 */
+	if (flags & KFD_IOC_ALLOC_MEM_FLAGS_VRAM) {
+		domain = alloc_domain = AMDGPU_GEM_DOMAIN_VRAM;
+		alloc_flags = AMDGPU_GEM_CREATE_VRAM_WIPE_ON_RELEASE;
+		alloc_flags |= (flags & KFD_IOC_ALLOC_MEM_FLAGS_PUBLIC) ?
+			AMDGPU_GEM_CREATE_CPU_ACCESS_REQUIRED : 0;
+	} else if (flags & KFD_IOC_ALLOC_MEM_FLAGS_GTT) {
+		domain = alloc_domain = AMDGPU_GEM_DOMAIN_GTT;
+		alloc_flags = 0;
+	} else {
+		domain = AMDGPU_GEM_DOMAIN_GTT;
+		alloc_domain = AMDGPU_GEM_DOMAIN_CPU;
+		alloc_flags = AMDGPU_GEM_CREATE_PREEMPTIBLE;
+
+		if (flags & KFD_IOC_ALLOC_MEM_FLAGS_USERPTR) {
+			if (!offset || !*offset)
+				return -EINVAL;
+			user_addr = untagged_addr(*offset);
+		} else if (flags & (KFD_IOC_ALLOC_MEM_FLAGS_DOORBELL |
+				    KFD_IOC_ALLOC_MEM_FLAGS_MMIO_REMAP)) {
+			bo_type = ttm_bo_type_sg;
+			if (size > UINT_MAX)
+				return -EINVAL;
+			sg = create_sg_table(*offset, size);
+			if (!sg)
+				return -ENOMEM;
+		} else {
+			return -EINVAL;
+		}
+	}
+
+	*mem = kzalloc(sizeof(struct kgd_mem), GFP_KERNEL);
+	if (!*mem) {
+		ret = -ENOMEM;
+		goto err;
+	}
+	INIT_LIST_HEAD(&(*mem)->attachments);
+	mutex_init(&(*mem)->lock);
+	(*mem)->aql_queue = !!(flags & KFD_IOC_ALLOC_MEM_FLAGS_AQL_QUEUE_MEM);
+
+	/* Workaround for AQL queue wraparound bug. Map the same
+	 * memory twice. That means we only actually allocate half
+	 * the memory.
+	 */
+	if ((*mem)->aql_queue)
+		size >>= 1;
+	aligned_size = PAGE_ALIGN(size);
+
+	(*mem)->alloc_flags = flags;
+
+	amdgpu_sync_create(&(*mem)->sync);
+
+	ret = amdgpu_amdkfd_reserve_mem_limit(adev, aligned_size, flags);
+	if (ret) {
+		pr_debug("Insufficient memory\n");
+		goto err_reserve_limit;
+	}
+
+	pr_debug("\tcreate BO VA 0x%llx size 0x%llx domain %s\n",
+			va, (*mem)->aql_queue ? size << 1 : size, domain_string(alloc_domain));
+
+	ret = amdgpu_gem_object_create(adev, aligned_size, 1, alloc_domain, alloc_flags,
+				       bo_type, NULL, &gobj);
+	if (ret) {
+		pr_debug("Failed to create BO on domain %s. ret %d\n",
+			 domain_string(alloc_domain), ret);
+		goto err_bo_create;
+	}
+	ret = drm_vma_node_allow(&gobj->vma_node, drm_priv);
+	if (ret) {
+		pr_debug("Failed to allow vma node access. ret %d\n", ret);
+		goto err_node_allow;
+	}
+	bo = gem_to_amdgpu_bo(gobj);
+	if (bo_type == ttm_bo_type_sg) {
+		bo->tbo.sg = sg;
+		bo->tbo.ttm->sg = sg;
+	}
+	bo->kfd_bo = *mem;
+	(*mem)->bo = bo;
+	if (user_addr)
+		bo->flags |= AMDGPU_AMDKFD_CREATE_USERPTR_BO;
+
+	(*mem)->va = va;
+	(*mem)->domain = domain;
+	(*mem)->mapped_to_gpu_memory = 0;
+	(*mem)->process_info = avm->process_info;
+	add_kgd_mem_to_kfd_bo_list(*mem, avm->process_info, user_addr);
+
+	if (user_addr) {
+		pr_debug("creating userptr BO for user_addr = %llx\n", user_addr);
+		ret = init_user_pages(*mem, user_addr, criu_resume);
+		if (ret)
+			goto allocate_init_user_pages_failed;
+	} else  if (flags & (KFD_IOC_ALLOC_MEM_FLAGS_DOORBELL |
+				KFD_IOC_ALLOC_MEM_FLAGS_MMIO_REMAP)) {
+		ret = amdgpu_amdkfd_gpuvm_pin_bo(bo, AMDGPU_GEM_DOMAIN_GTT);
+		if (ret) {
+			pr_err("Pinning MMIO/DOORBELL BO during ALLOC FAILED\n");
+			goto err_pin_bo;
+		}
+		bo->allowed_domains = AMDGPU_GEM_DOMAIN_GTT;
+		bo->preferred_domains = AMDGPU_GEM_DOMAIN_GTT;
+	}
+
+	if (offset)
+		*offset = amdgpu_bo_mmap_offset(bo);
+
+	return 0;
+
+allocate_init_user_pages_failed:
+err_pin_bo:
+	remove_kgd_mem_from_kfd_bo_list(*mem, avm->process_info);
+	drm_vma_node_revoke(&gobj->vma_node, drm_priv);
+err_node_allow:
+	/* Don't unreserve system mem limit twice */
+	goto err_reserve_limit;
+err_bo_create:
+	amdgpu_amdkfd_unreserve_mem_limit(adev, aligned_size, flags);
+err_reserve_limit:
+	mutex_destroy(&(*mem)->lock);
+	if (gobj)
+		drm_gem_object_put(gobj);
+	else
+		kfree(*mem);
+err:
+	if (sg) {
+		sg_free_table(sg);
+		kfree(sg);
+	}
+	return ret;
+}
+
+int amdgpu_amdkfd_gpuvm_free_memory_of_gpu(
+		struct amdgpu_device *adev, struct kgd_mem *mem, void *drm_priv,
+		uint64_t *size)
+{
+	struct amdkfd_process_info *process_info = mem->process_info;
+	unsigned long bo_size = mem->bo->tbo.base.size;
+	bool use_release_notifier = (mem->bo->kfd_bo == mem);
+	struct kfd_mem_attachment *entry, *tmp;
+	struct bo_vm_reservation_context ctx;
+	struct ttm_validate_buffer *bo_list_entry;
+	unsigned int mapped_to_gpu_memory;
+	int ret;
+	bool is_imported = false;
+
+	mutex_lock(&mem->lock);
+
+	/* Unpin MMIO/DOORBELL BO's that were pinned during allocation */
+	if (mem->alloc_flags &
+	    (KFD_IOC_ALLOC_MEM_FLAGS_DOORBELL |
+	     KFD_IOC_ALLOC_MEM_FLAGS_MMIO_REMAP)) {
+		amdgpu_amdkfd_gpuvm_unpin_bo(mem->bo);
+	}
+
+	mapped_to_gpu_memory = mem->mapped_to_gpu_memory;
+	is_imported = mem->is_imported;
+	mutex_unlock(&mem->lock);
+	/* lock is not needed after this, since mem is unused and will
+	 * be freed anyway
+	 */
+
+	if (mapped_to_gpu_memory > 0) {
+		pr_debug("BO VA 0x%llx size 0x%lx is still mapped.\n",
+				mem->va, bo_size);
+		return -EBUSY;
+	}
+
+	/* Make sure restore workers don't access the BO any more */
+	bo_list_entry = &mem->validate_list;
+	mutex_lock(&process_info->lock);
+	list_del(&bo_list_entry->head);
+	mutex_unlock(&process_info->lock);
+
+	/* No more MMU notifiers */
+	amdgpu_mn_unregister(mem->bo);
+
+	ret = reserve_bo_and_cond_vms(mem, NULL, BO_VM_ALL, &ctx);
+	if (unlikely(ret))
+		return ret;
+
+	/* The eviction fence should be removed by the last unmap.
+	 * TODO: Log an error condition if the bo still has the eviction fence
+	 * attached
+	 */
+	amdgpu_amdkfd_remove_eviction_fence(mem->bo,
+					process_info->eviction_fence);
+	pr_debug("Release VA 0x%llx - 0x%llx\n", mem->va,
+		mem->va + bo_size * (1 + mem->aql_queue));
+
+	/* Remove from VM internal data structures */
+	list_for_each_entry_safe(entry, tmp, &mem->attachments, list)
+		kfd_mem_detach(entry);
+
+	ret = unreserve_bo_and_vms(&ctx, false, false);
+
+	/* Free the sync object */
+	amdgpu_sync_free(&mem->sync);
+
+	/* If the SG is not NULL, it's one we created for a doorbell or mmio
+	 * remap BO. We need to free it.
+	 */
+	if (mem->bo->tbo.sg) {
+		sg_free_table(mem->bo->tbo.sg);
+		kfree(mem->bo->tbo.sg);
+	}
+
+	/* Update the size of the BO being freed if it was allocated from
+	 * VRAM and is not imported.
+	 */
+	if (size) {
+		if ((mem->bo->preferred_domains == AMDGPU_GEM_DOMAIN_VRAM) &&
+		    (!is_imported))
+			*size = bo_size;
+		else
+			*size = 0;
+	}
+
+	/* Free the BO*/
+	drm_vma_node_revoke(&mem->bo->tbo.base.vma_node, drm_priv);
+	if (mem->dmabuf)
+		dma_buf_put(mem->dmabuf);
+	mutex_destroy(&mem->lock);
+
+	/* If this releases the last reference, it will end up calling
+	 * amdgpu_amdkfd_release_notify and kfree the mem struct. That's why
+	 * this needs to be the last call here.
+	 */
+	drm_gem_object_put(&mem->bo->tbo.base);
+
+	/*
+	 * For kgd_mem allocated in amdgpu_amdkfd_gpuvm_import_dmabuf(),
+	 * explicitly free it here.
+	 */
+	if (!use_release_notifier)
+		kfree(mem);
+
+	return ret;
+}
+
+int amdgpu_amdkfd_gpuvm_map_memory_to_gpu(
+		struct amdgpu_device *adev, struct kgd_mem *mem,
+		void *drm_priv)
+{
+	struct amdgpu_vm *avm = drm_priv_to_vm(drm_priv);
+	int ret;
+	struct amdgpu_bo *bo;
+	uint32_t domain;
+	struct kfd_mem_attachment *entry;
+	struct bo_vm_reservation_context ctx;
+	unsigned long bo_size;
+	bool is_invalid_userptr = false;
+
+	bo = mem->bo;
+	if (!bo) {
+		pr_err("Invalid BO when mapping memory to GPU\n");
+		return -EINVAL;
+	}
+
+	/* Make sure restore is not running concurrently. Since we
+	 * don't map invalid userptr BOs, we rely on the next restore
+	 * worker to do the mapping
+	 */
+	mutex_lock(&mem->process_info->lock);
+
+	/* Lock mmap-sem. If we find an invalid userptr BO, we can be
+	 * sure that the MMU notifier is no longer running
+	 * concurrently and the queues are actually stopped
+	 */
+	if (amdgpu_ttm_tt_get_usermm(bo->tbo.ttm)) {
+		mmap_write_lock(current->mm);
+		is_invalid_userptr = atomic_read(&mem->invalid);
+		mmap_write_unlock(current->mm);
+	}
+
+	mutex_lock(&mem->lock);
+
+	domain = mem->domain;
+	bo_size = bo->tbo.base.size;
+
+	pr_debug("Map VA 0x%llx - 0x%llx to vm %p domain %s\n",
+			mem->va,
+			mem->va + bo_size * (1 + mem->aql_queue),
+			avm, domain_string(domain));
+
+	if (!kfd_mem_is_attached(avm, mem)) {
+		ret = kfd_mem_attach(adev, mem, avm, mem->aql_queue);
+		if (ret)
+			goto out;
+	}
+
+	ret = reserve_bo_and_vm(mem, avm, &ctx);
+	if (unlikely(ret))
+		goto out;
+
+	/* Userptr can be marked as "not invalid", but not actually be
+	 * validated yet (still in the system domain). In that case
+	 * the queues are still stopped and we can leave mapping for
+	 * the next restore worker
+	 */
+	if (amdgpu_ttm_tt_get_usermm(bo->tbo.ttm) &&
+	    bo->tbo.resource->mem_type == TTM_PL_SYSTEM)
+		is_invalid_userptr = true;
+
+	ret = vm_validate_pt_pd_bos(avm);
+	if (unlikely(ret))
+		goto out_unreserve;
+
+	if (mem->mapped_to_gpu_memory == 0 &&
+	    !amdgpu_ttm_tt_get_usermm(bo->tbo.ttm)) {
+		/* Validate BO only once. The eviction fence gets added to BO
+		 * the first time it is mapped. Validate will wait for all
+		 * background evictions to complete.
+		 */
+		ret = amdgpu_amdkfd_bo_validate(bo, domain, true);
+		if (ret) {
+			pr_debug("Validate failed\n");
+			goto out_unreserve;
+		}
+	}
+
+	list_for_each_entry(entry, &mem->attachments, list) {
+		if (entry->bo_va->base.vm != avm || entry->is_mapped)
+			continue;
+
+		pr_debug("\t map VA 0x%llx - 0x%llx in entry %p\n",
+			 entry->va, entry->va + bo_size, entry);
+
+		ret = map_bo_to_gpuvm(mem, entry, ctx.sync,
+				      is_invalid_userptr);
+		if (ret) {
+			pr_err("Failed to map bo to gpuvm\n");
+			goto out_unreserve;
+		}
+
+		ret = vm_update_pds(avm, ctx.sync);
+		if (ret) {
+			pr_err("Failed to update page directories\n");
+			goto out_unreserve;
+		}
+
+		entry->is_mapped = true;
+		mem->mapped_to_gpu_memory++;
+		pr_debug("\t INC mapping count %d\n",
+			 mem->mapped_to_gpu_memory);
+	}
+
+	if (!amdgpu_ttm_tt_get_usermm(bo->tbo.ttm) && !bo->tbo.pin_count)
+		dma_resv_add_fence(bo->tbo.base.resv,
+				   &avm->process_info->eviction_fence->base,
+				   DMA_RESV_USAGE_BOOKKEEP);
+	ret = unreserve_bo_and_vms(&ctx, false, false);
+
+	goto out;
+
+out_unreserve:
+	unreserve_bo_and_vms(&ctx, false, false);
+out:
+	mutex_unlock(&mem->process_info->lock);
+	mutex_unlock(&mem->lock);
+	return ret;
+}
+
+int amdgpu_amdkfd_gpuvm_unmap_memory_from_gpu(
+		struct amdgpu_device *adev, struct kgd_mem *mem, void *drm_priv)
+{
+	struct amdgpu_vm *avm = drm_priv_to_vm(drm_priv);
+	struct amdkfd_process_info *process_info = avm->process_info;
+	unsigned long bo_size = mem->bo->tbo.base.size;
+	struct kfd_mem_attachment *entry;
+	struct bo_vm_reservation_context ctx;
+	int ret;
+
+	mutex_lock(&mem->lock);
+
+	ret = reserve_bo_and_cond_vms(mem, avm, BO_VM_MAPPED, &ctx);
+	if (unlikely(ret))
+		goto out;
+	/* If no VMs were reserved, it means the BO wasn't actually mapped */
+	if (ctx.n_vms == 0) {
+		ret = -EINVAL;
+		goto unreserve_out;
+	}
+
+	ret = vm_validate_pt_pd_bos(avm);
+	if (unlikely(ret))
+		goto unreserve_out;
+
+	pr_debug("Unmap VA 0x%llx - 0x%llx from vm %p\n",
+		mem->va,
+		mem->va + bo_size * (1 + mem->aql_queue),
+		avm);
+
+	list_for_each_entry(entry, &mem->attachments, list) {
+		if (entry->bo_va->base.vm != avm || !entry->is_mapped)
+			continue;
+
+		pr_debug("\t unmap VA 0x%llx - 0x%llx from entry %p\n",
+			 entry->va, entry->va + bo_size, entry);
+
+		unmap_bo_from_gpuvm(mem, entry, ctx.sync);
+		entry->is_mapped = false;
+
+		mem->mapped_to_gpu_memory--;
+		pr_debug("\t DEC mapping count %d\n",
+			 mem->mapped_to_gpu_memory);
+	}
+
+	/* If BO is unmapped from all VMs, unfence it. It can be evicted if
+	 * required.
+	 */
+	if (mem->mapped_to_gpu_memory == 0 &&
+	    !amdgpu_ttm_tt_get_usermm(mem->bo->tbo.ttm) &&
+	    !mem->bo->tbo.pin_count)
+		amdgpu_amdkfd_remove_eviction_fence(mem->bo,
+						process_info->eviction_fence);
+
+unreserve_out:
+	unreserve_bo_and_vms(&ctx, false, false);
+out:
+	mutex_unlock(&mem->lock);
+	return ret;
+}
+
+int amdgpu_amdkfd_gpuvm_sync_memory(
+		struct amdgpu_device *adev, struct kgd_mem *mem, bool intr)
+{
+	struct amdgpu_sync sync;
+	int ret;
+
+	amdgpu_sync_create(&sync);
+
+	mutex_lock(&mem->lock);
+	amdgpu_sync_clone(&mem->sync, &sync);
+	mutex_unlock(&mem->lock);
+
+	ret = amdgpu_sync_wait(&sync, intr);
+	amdgpu_sync_free(&sync);
+	return ret;
+}
+
+/**
+ * amdgpu_amdkfd_map_gtt_bo_to_gart - Map BO to GART and increment reference count
+ * @adev: Device to which allocated BO belongs
+ * @bo: Buffer object to be mapped
+ *
+ * Before return, bo reference count is incremented. To release the reference and unpin/
+ * unmap the BO, call amdgpu_amdkfd_free_gtt_mem.
+ */
+int amdgpu_amdkfd_map_gtt_bo_to_gart(struct amdgpu_device *adev, struct amdgpu_bo *bo)
+{
+	int ret;
+
+	ret = amdgpu_bo_reserve(bo, true);
+	if (ret) {
+		pr_err("Failed to reserve bo. ret %d\n", ret);
+		goto err_reserve_bo_failed;
+	}
+
+	ret = amdgpu_bo_pin(bo, AMDGPU_GEM_DOMAIN_GTT);
+	if (ret) {
+		pr_err("Failed to pin bo. ret %d\n", ret);
+		goto err_pin_bo_failed;
+	}
+
+	ret = amdgpu_ttm_alloc_gart(&bo->tbo);
+	if (ret) {
+		pr_err("Failed to bind bo to GART. ret %d\n", ret);
+		goto err_map_bo_gart_failed;
+	}
+
+	amdgpu_amdkfd_remove_eviction_fence(
+		bo, bo->vm_bo->vm->process_info->eviction_fence);
+
+	amdgpu_bo_unreserve(bo);
+
+	bo = amdgpu_bo_ref(bo);
+
+	return 0;
+
+err_map_bo_gart_failed:
+	amdgpu_bo_unpin(bo);
+err_pin_bo_failed:
+	amdgpu_bo_unreserve(bo);
+err_reserve_bo_failed:
+
+	return ret;
+}
+
+/** amdgpu_amdkfd_gpuvm_map_gtt_bo_to_kernel() - Map a GTT BO for kernel CPU access
+ *
+ * @mem: Buffer object to be mapped for CPU access
+ * @kptr[out]: pointer in kernel CPU address space
+ * @size[out]: size of the buffer
+ *
+ * Pins the BO and maps it for kernel CPU access. The eviction fence is removed
+ * from the BO, since pinned BOs cannot be evicted. The bo must remain on the
+ * validate_list, so the GPU mapping can be restored after a page table was
+ * evicted.
+ *
+ * Return: 0 on success, error code on failure
+ */
+int amdgpu_amdkfd_gpuvm_map_gtt_bo_to_kernel(struct kgd_mem *mem,
+					     void **kptr, uint64_t *size)
+{
+	int ret;
+	struct amdgpu_bo *bo = mem->bo;
+
+	if (amdgpu_ttm_tt_get_usermm(bo->tbo.ttm)) {
+		pr_err("userptr can't be mapped to kernel\n");
+		return -EINVAL;
+	}
+
+	mutex_lock(&mem->process_info->lock);
+
+	ret = amdgpu_bo_reserve(bo, true);
+	if (ret) {
+		pr_err("Failed to reserve bo. ret %d\n", ret);
+		goto bo_reserve_failed;
+	}
+
+	ret = amdgpu_bo_pin(bo, AMDGPU_GEM_DOMAIN_GTT);
+	if (ret) {
+		pr_err("Failed to pin bo. ret %d\n", ret);
+		goto pin_failed;
+	}
+
+	ret = amdgpu_bo_kmap(bo, kptr);
+	if (ret) {
+		pr_err("Failed to map bo to kernel. ret %d\n", ret);
+		goto kmap_failed;
+	}
+
+	amdgpu_amdkfd_remove_eviction_fence(
+		bo, mem->process_info->eviction_fence);
+
+	if (size)
+		*size = amdgpu_bo_size(bo);
+
+	amdgpu_bo_unreserve(bo);
+
+	mutex_unlock(&mem->process_info->lock);
+	return 0;
+
+kmap_failed:
+	amdgpu_bo_unpin(bo);
+pin_failed:
+	amdgpu_bo_unreserve(bo);
+bo_reserve_failed:
+	mutex_unlock(&mem->process_info->lock);
+
+	return ret;
+}
+
+/** amdgpu_amdkfd_gpuvm_map_gtt_bo_to_kernel() - Unmap a GTT BO for kernel CPU access
+ *
+ * @mem: Buffer object to be unmapped for CPU access
+ *
+ * Removes the kernel CPU mapping and unpins the BO. It does not restore the
+ * eviction fence, so this function should only be used for cleanup before the
+ * BO is destroyed.
+ */
+void amdgpu_amdkfd_gpuvm_unmap_gtt_bo_from_kernel(struct kgd_mem *mem)
+{
+	struct amdgpu_bo *bo = mem->bo;
+
+	amdgpu_bo_reserve(bo, true);
+	amdgpu_bo_kunmap(bo);
+	amdgpu_bo_unpin(bo);
+	amdgpu_bo_unreserve(bo);
+}
+
+int amdgpu_amdkfd_gpuvm_get_vm_fault_info(struct amdgpu_device *adev,
+					  struct kfd_vm_fault_info *mem)
+{
+	if (atomic_read(&adev->gmc.vm_fault_info_updated) == 1) {
+		*mem = *adev->gmc.vm_fault_info;
+		mb(); /* make sure read happened */
+		atomic_set(&adev->gmc.vm_fault_info_updated, 0);
+	}
+	return 0;
+}
+
+int amdgpu_amdkfd_gpuvm_import_dmabuf(struct amdgpu_device *adev,
+				      struct dma_buf *dma_buf,
+				      uint64_t va, void *drm_priv,
+				      struct kgd_mem **mem, uint64_t *size,
+				      uint64_t *mmap_offset)
+{
+	struct amdgpu_vm *avm = drm_priv_to_vm(drm_priv);
+	struct drm_gem_object *obj;
+	struct amdgpu_bo *bo;
+	int ret;
+
+	if (dma_buf->ops != &amdgpu_dmabuf_ops)
+		/* Can't handle non-graphics buffers */
+		return -EINVAL;
+
+	obj = dma_buf->priv;
+	if (drm_to_adev(obj->dev) != adev)
+		/* Can't handle buffers from other devices */
+		return -EINVAL;
+
+	bo = gem_to_amdgpu_bo(obj);
+	if (!(bo->preferred_domains & (AMDGPU_GEM_DOMAIN_VRAM |
+				    AMDGPU_GEM_DOMAIN_GTT)))
+		/* Only VRAM and GTT BOs are supported */
+		return -EINVAL;
+
+	*mem = kzalloc(sizeof(struct kgd_mem), GFP_KERNEL);
+	if (!*mem)
+		return -ENOMEM;
+
+	ret = drm_vma_node_allow(&obj->vma_node, drm_priv);
+	if (ret) {
+		kfree(*mem);
+		return ret;
+	}
+
+	if (size)
+		*size = amdgpu_bo_size(bo);
+
+	if (mmap_offset)
+		*mmap_offset = amdgpu_bo_mmap_offset(bo);
+
+	INIT_LIST_HEAD(&(*mem)->attachments);
+	mutex_init(&(*mem)->lock);
+
+	(*mem)->alloc_flags =
+		((bo->preferred_domains & AMDGPU_GEM_DOMAIN_VRAM) ?
+		KFD_IOC_ALLOC_MEM_FLAGS_VRAM : KFD_IOC_ALLOC_MEM_FLAGS_GTT)
+		| KFD_IOC_ALLOC_MEM_FLAGS_WRITABLE
+		| KFD_IOC_ALLOC_MEM_FLAGS_EXECUTABLE;
+
+	drm_gem_object_get(&bo->tbo.base);
+	(*mem)->bo = bo;
+	(*mem)->va = va;
+	(*mem)->domain = (bo->preferred_domains & AMDGPU_GEM_DOMAIN_VRAM) ?
+		AMDGPU_GEM_DOMAIN_VRAM : AMDGPU_GEM_DOMAIN_GTT;
+	(*mem)->mapped_to_gpu_memory = 0;
+	(*mem)->process_info = avm->process_info;
+	add_kgd_mem_to_kfd_bo_list(*mem, avm->process_info, false);
+	amdgpu_sync_create(&(*mem)->sync);
+	(*mem)->is_imported = true;
+
+	return 0;
+}
+
+/* Evict a userptr BO by stopping the queues if necessary
+ *
+ * Runs in MMU notifier, may be in RECLAIM_FS context. This means it
+ * cannot do any memory allocations, and cannot take any locks that
+ * are held elsewhere while allocating memory. Therefore this is as
+ * simple as possible, using atomic counters.
+ *
+ * It doesn't do anything to the BO itself. The real work happens in
+ * restore, where we get updated page addresses. This function only
+ * ensures that GPU access to the BO is stopped.
+ */
+int amdgpu_amdkfd_evict_userptr(struct kgd_mem *mem,
+				struct mm_struct *mm)
+{
+	struct amdkfd_process_info *process_info = mem->process_info;
+	int evicted_bos;
+	int r = 0;
+
+	/* Do not process MMU notifications until stage-4 IOCTL is received */
+	if (READ_ONCE(process_info->block_mmu_notifications))
+		return 0;
+
+	atomic_inc(&mem->invalid);
+	evicted_bos = atomic_inc_return(&process_info->evicted_bos);
+	if (evicted_bos == 1) {
+		/* First eviction, stop the queues */
+		r = kgd2kfd_quiesce_mm(mm, KFD_QUEUE_EVICTION_TRIGGER_USERPTR);
+		if (r)
+			pr_err("Failed to quiesce KFD\n");
+		schedule_delayed_work(&process_info->restore_userptr_work,
+			msecs_to_jiffies(AMDGPU_USERPTR_RESTORE_DELAY_MS));
+	}
+
+	return r;
+}
+
+/* Update invalid userptr BOs
+ *
+ * Moves invalidated (evicted) userptr BOs from userptr_valid_list to
+ * userptr_inval_list and updates user pages for all BOs that have
+ * been invalidated since their last update.
+ */
+static int update_invalid_user_pages(struct amdkfd_process_info *process_info,
+				     struct mm_struct *mm)
+{
+	struct kgd_mem *mem, *tmp_mem;
+	struct amdgpu_bo *bo;
+	struct ttm_operation_ctx ctx = { false, false };
+	int invalid, ret;
+
+	/* Move all invalidated BOs to the userptr_inval_list and
+	 * release their user pages by migration to the CPU domain
+	 */
+	list_for_each_entry_safe(mem, tmp_mem,
+				 &process_info->userptr_valid_list,
+				 validate_list.head) {
+		if (!atomic_read(&mem->invalid))
+			continue; /* BO is still valid */
+
+		bo = mem->bo;
+
+		if (amdgpu_bo_reserve(bo, true))
+			return -EAGAIN;
+		amdgpu_bo_placement_from_domain(bo, AMDGPU_GEM_DOMAIN_CPU);
+		ret = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
+		amdgpu_bo_unreserve(bo);
+		if (ret) {
+			pr_err("%s: Failed to invalidate userptr BO\n",
+			       __func__);
+			return -EAGAIN;
+		}
+
+		list_move_tail(&mem->validate_list.head,
+			       &process_info->userptr_inval_list);
+	}
+
+	if (list_empty(&process_info->userptr_inval_list))
+		return 0; /* All evicted userptr BOs were freed */
+
+	/* Go through userptr_inval_list and update any invalid user_pages */
+	list_for_each_entry(mem, &process_info->userptr_inval_list,
+			    validate_list.head) {
+		struct hmm_range *range;
+
+		invalid = atomic_read(&mem->invalid);
+		if (!invalid)
+			/* BO hasn't been invalidated since the last
+			 * revalidation attempt. Keep its BO list.
+			 */
+			continue;
+
+		bo = mem->bo;
+
+		/* Get updated user pages */
+		ret = amdgpu_ttm_tt_get_user_pages(bo, bo->tbo.ttm->pages,
+						   &range);
+		if (ret) {
+			pr_debug("Failed %d to get user pages\n", ret);
+
+			/* Return -EFAULT bad address error as success. It will
+			 * fail later with a VM fault if the GPU tries to access
+			 * it. Better than hanging indefinitely with stalled
+			 * user mode queues.
+			 *
+			 * Return other error -EBUSY or -ENOMEM to retry restore
+			 */
+			if (ret != -EFAULT)
+				return ret;
+		} else {
+
+			/*
+			 * FIXME: Cannot ignore the return code, must hold
+			 * notifier_lock
+			 */
+			amdgpu_ttm_tt_get_user_pages_done(bo->tbo.ttm, range);
+		}
+
+		/* Mark the BO as valid unless it was invalidated
+		 * again concurrently.
+		 */
+		if (atomic_cmpxchg(&mem->invalid, invalid, 0) != invalid)
+			return -EAGAIN;
+	}
+
+	return 0;
+}
+
+/* Validate invalid userptr BOs
+ *
+ * Validates BOs on the userptr_inval_list, and moves them back to the
+ * userptr_valid_list. Also updates GPUVM page tables with new page
+ * addresses and waits for the page table updates to complete.
+ */
+static int validate_invalid_user_pages(struct amdkfd_process_info *process_info)
+{
+	struct amdgpu_bo_list_entry *pd_bo_list_entries;
+	struct list_head resv_list, duplicates;
+	struct ww_acquire_ctx ticket;
+	struct amdgpu_sync sync;
+
+	struct amdgpu_vm *peer_vm;
+	struct kgd_mem *mem, *tmp_mem;
+	struct amdgpu_bo *bo;
+	struct ttm_operation_ctx ctx = { false, false };
+	int i, ret;
+
+	pd_bo_list_entries = kcalloc(process_info->n_vms,
+				     sizeof(struct amdgpu_bo_list_entry),
+				     GFP_KERNEL);
+	if (!pd_bo_list_entries) {
+		pr_err("%s: Failed to allocate PD BO list entries\n", __func__);
+		ret = -ENOMEM;
+		goto out_no_mem;
+	}
+
+	INIT_LIST_HEAD(&resv_list);
+	INIT_LIST_HEAD(&duplicates);
+
+	/* Get all the page directory BOs that need to be reserved */
+	i = 0;
+	list_for_each_entry(peer_vm, &process_info->vm_list_head,
+			    vm_list_node)
+		amdgpu_vm_get_pd_bo(peer_vm, &resv_list,
+				    &pd_bo_list_entries[i++]);
+	/* Add the userptr_inval_list entries to resv_list */
+	list_for_each_entry(mem, &process_info->userptr_inval_list,
+			    validate_list.head) {
+		list_add_tail(&mem->resv_list.head, &resv_list);
+		mem->resv_list.bo = mem->validate_list.bo;
+		mem->resv_list.num_shared = mem->validate_list.num_shared;
+	}
+
+	/* Reserve all BOs and page tables for validation */
+	ret = ttm_eu_reserve_buffers(&ticket, &resv_list, false, &duplicates);
+	WARN(!list_empty(&duplicates), "Duplicates should be empty");
+	if (ret)
+		goto out_free;
+
+	amdgpu_sync_create(&sync);
+
+	ret = process_validate_vms(process_info);
+	if (ret)
+		goto unreserve_out;
+
+	/* Validate BOs and update GPUVM page tables */
+	list_for_each_entry_safe(mem, tmp_mem,
+				 &process_info->userptr_inval_list,
+				 validate_list.head) {
+		struct kfd_mem_attachment *attachment;
+
+		bo = mem->bo;
+
+		/* Validate the BO if we got user pages */
+		if (bo->tbo.ttm->pages[0]) {
+			amdgpu_bo_placement_from_domain(bo, mem->domain);
+			ret = ttm_bo_validate(&bo->tbo, &bo->placement, &ctx);
+			if (ret) {
+				pr_err("%s: failed to validate BO\n", __func__);
+				goto unreserve_out;
+			}
+		}
+
+		list_move_tail(&mem->validate_list.head,
+			       &process_info->userptr_valid_list);
+
+		/* Update mapping. If the BO was not validated
+		 * (because we couldn't get user pages), this will
+		 * clear the page table entries, which will result in
+		 * VM faults if the GPU tries to access the invalid
+		 * memory.
+		 */
+		list_for_each_entry(attachment, &mem->attachments, list) {
+			if (!attachment->is_mapped)
+				continue;
+
+			kfd_mem_dmaunmap_attachment(mem, attachment);
+			ret = update_gpuvm_pte(mem, attachment, &sync);
+			if (ret) {
+				pr_err("%s: update PTE failed\n", __func__);
+				/* make sure this gets validated again */
+				atomic_inc(&mem->invalid);
+				goto unreserve_out;
+			}
+		}
+	}
+
+	/* Update page directories */
+	ret = process_update_pds(process_info, &sync);
+
+unreserve_out:
+	ttm_eu_backoff_reservation(&ticket, &resv_list);
+	amdgpu_sync_wait(&sync, false);
+	amdgpu_sync_free(&sync);
+out_free:
+	kfree(pd_bo_list_entries);
+out_no_mem:
+
+	return ret;
+}
+
+/* Worker callback to restore evicted userptr BOs
+ *
+ * Tries to update and validate all userptr BOs. If successful and no
+ * concurrent evictions happened, the queues are restarted. Otherwise,
+ * reschedule for another attempt later.
+ */
+static void amdgpu_amdkfd_restore_userptr_worker(struct work_struct *work)
+{
+	struct delayed_work *dwork = to_delayed_work(work);
+	struct amdkfd_process_info *process_info =
+		container_of(dwork, struct amdkfd_process_info,
+			     restore_userptr_work);
+	struct task_struct *usertask;
+	struct mm_struct *mm;
+	int evicted_bos;
+
+	evicted_bos = atomic_read(&process_info->evicted_bos);
+	if (!evicted_bos)
+		return;
+
+	/* Reference task and mm in case of concurrent process termination */
+	usertask = get_pid_task(process_info->pid, PIDTYPE_PID);
+	if (!usertask)
+		return;
+	mm = get_task_mm(usertask);
+	if (!mm) {
+		put_task_struct(usertask);
+		return;
+	}
+
+	mutex_lock(&process_info->lock);
+
+	if (update_invalid_user_pages(process_info, mm))
+		goto unlock_out;
+	/* userptr_inval_list can be empty if all evicted userptr BOs
+	 * have been freed. In that case there is nothing to validate
+	 * and we can just restart the queues.
+	 */
+	if (!list_empty(&process_info->userptr_inval_list)) {
+		if (atomic_read(&process_info->evicted_bos) != evicted_bos)
+			goto unlock_out; /* Concurrent eviction, try again */
+
+		if (validate_invalid_user_pages(process_info))
+			goto unlock_out;
+	}
+	/* Final check for concurrent evicton and atomic update. If
+	 * another eviction happens after successful update, it will
+	 * be a first eviction that calls quiesce_mm. The eviction
+	 * reference counting inside KFD will handle this case.
+	 */
+	if (atomic_cmpxchg(&process_info->evicted_bos, evicted_bos, 0) !=
+	    evicted_bos)
+		goto unlock_out;
+	evicted_bos = 0;
+	if (kgd2kfd_resume_mm(mm)) {
+		pr_err("%s: Failed to resume KFD\n", __func__);
+		/* No recovery from this failure. Probably the CP is
+		 * hanging. No point trying again.
+		 */
+	}
+
+unlock_out:
+	mutex_unlock(&process_info->lock);
+
+	/* If validation failed, reschedule another attempt */
+	if (evicted_bos) {
+		schedule_delayed_work(&process_info->restore_userptr_work,
+			msecs_to_jiffies(AMDGPU_USERPTR_RESTORE_DELAY_MS));
+
+		kfd_smi_event_queue_restore_rescheduled(mm);
+	}
+	mmput(mm);
+	put_task_struct(usertask);
+}
+
+/** amdgpu_amdkfd_gpuvm_restore_process_bos - Restore all BOs for the given
+ *   KFD process identified by process_info
+ *
+ * @process_info: amdkfd_process_info of the KFD process
+ *
+ * After memory eviction, restore thread calls this function. The function
+ * should be called when the Process is still valid. BO restore involves -
+ *
+ * 1.  Release old eviction fence and create new one
+ * 2.  Get two copies of PD BO list from all the VMs. Keep one copy as pd_list.
+ * 3   Use the second PD list and kfd_bo_list to create a list (ctx.list) of
+ *     BOs that need to be reserved.
+ * 4.  Reserve all the BOs
+ * 5.  Validate of PD and PT BOs.
+ * 6.  Validate all KFD BOs using kfd_bo_list and Map them and add new fence
+ * 7.  Add fence to all PD and PT BOs.
+ * 8.  Unreserve all BOs
+ */
+int amdgpu_amdkfd_gpuvm_restore_process_bos(void *info, struct dma_fence **ef)
+{
+	struct amdgpu_bo_list_entry *pd_bo_list;
+	struct amdkfd_process_info *process_info = info;
+	struct amdgpu_vm *peer_vm;
+	struct kgd_mem *mem;
+	struct bo_vm_reservation_context ctx;
+	struct amdgpu_amdkfd_fence *new_fence;
+	int ret = 0, i;
+	struct list_head duplicate_save;
+	struct amdgpu_sync sync_obj;
+	unsigned long failed_size = 0;
+	unsigned long total_size = 0;
+
+	INIT_LIST_HEAD(&duplicate_save);
+	INIT_LIST_HEAD(&ctx.list);
+	INIT_LIST_HEAD(&ctx.duplicates);
+
+	pd_bo_list = kcalloc(process_info->n_vms,
+			     sizeof(struct amdgpu_bo_list_entry),
+			     GFP_KERNEL);
+	if (!pd_bo_list)
+		return -ENOMEM;
+
+	i = 0;
+	mutex_lock(&process_info->lock);
+	list_for_each_entry(peer_vm, &process_info->vm_list_head,
+			vm_list_node)
+		amdgpu_vm_get_pd_bo(peer_vm, &ctx.list, &pd_bo_list[i++]);
+
+	/* Reserve all BOs and page tables/directory. Add all BOs from
+	 * kfd_bo_list to ctx.list
+	 */
+	list_for_each_entry(mem, &process_info->kfd_bo_list,
+			    validate_list.head) {
+
+		list_add_tail(&mem->resv_list.head, &ctx.list);
+		mem->resv_list.bo = mem->validate_list.bo;
+		mem->resv_list.num_shared = mem->validate_list.num_shared;
+	}
+
+	ret = ttm_eu_reserve_buffers(&ctx.ticket, &ctx.list,
+				     false, &duplicate_save);
+	if (ret) {
+		pr_debug("Memory eviction: TTM Reserve Failed. Try again\n");
+		goto ttm_reserve_fail;
+	}
+
+	amdgpu_sync_create(&sync_obj);
+
+	/* Validate PDs and PTs */
+	ret = process_validate_vms(process_info);
+	if (ret)
+		goto validate_map_fail;
+
+	ret = process_sync_pds_resv(process_info, &sync_obj);
+	if (ret) {
+		pr_debug("Memory eviction: Failed to sync to PD BO moving fence. Try again\n");
+		goto validate_map_fail;
+	}
+
+	/* Validate BOs and map them to GPUVM (update VM page tables). */
+	list_for_each_entry(mem, &process_info->kfd_bo_list,
+			    validate_list.head) {
+
+		struct amdgpu_bo *bo = mem->bo;
+		uint32_t domain = mem->domain;
+		struct kfd_mem_attachment *attachment;
+		struct dma_resv_iter cursor;
+		struct dma_fence *fence;
+
+		total_size += amdgpu_bo_size(bo);
+
+		ret = amdgpu_amdkfd_bo_validate(bo, domain, false);
+		if (ret) {
+			pr_debug("Memory eviction: Validate BOs failed\n");
+			failed_size += amdgpu_bo_size(bo);
+			ret = amdgpu_amdkfd_bo_validate(bo,
+						AMDGPU_GEM_DOMAIN_GTT, false);
+			if (ret) {
+				pr_debug("Memory eviction: Try again\n");
+				goto validate_map_fail;
+			}
+		}
+		dma_resv_for_each_fence(&cursor, bo->tbo.base.resv,
+					DMA_RESV_USAGE_KERNEL, fence) {
+			ret = amdgpu_sync_fence(&sync_obj, fence);
+			if (ret) {
+				pr_debug("Memory eviction: Sync BO fence failed. Try again\n");
+				goto validate_map_fail;
+			}
+		}
+		list_for_each_entry(attachment, &mem->attachments, list) {
+			if (!attachment->is_mapped)
+				continue;
+
+			if (attachment->bo_va->base.bo->tbo.pin_count)
+				continue;
+
+			kfd_mem_dmaunmap_attachment(mem, attachment);
+			ret = update_gpuvm_pte(mem, attachment, &sync_obj);
+			if (ret) {
+				pr_debug("Memory eviction: update PTE failed. Try again\n");
+				goto validate_map_fail;
+			}
+		}
+	}
+
+	if (failed_size)
+		pr_debug("0x%lx/0x%lx in system\n", failed_size, total_size);
+
+	/* Update page directories */
+	ret = process_update_pds(process_info, &sync_obj);
+	if (ret) {
+		pr_debug("Memory eviction: update PDs failed. Try again\n");
+		goto validate_map_fail;
+	}
+
+	/* Wait for validate and PT updates to finish */
+	amdgpu_sync_wait(&sync_obj, false);
+
+	/* Release old eviction fence and create new one, because fence only
+	 * goes from unsignaled to signaled, fence cannot be reused.
+	 * Use context and mm from the old fence.
+	 */
+	new_fence = amdgpu_amdkfd_fence_create(
+				process_info->eviction_fence->base.context,
+				process_info->eviction_fence->mm,
+				NULL);
+	if (!new_fence) {
+		pr_err("Failed to create eviction fence\n");
+		ret = -ENOMEM;
+		goto validate_map_fail;
+	}
+	dma_fence_put(&process_info->eviction_fence->base);
+	process_info->eviction_fence = new_fence;
+	*ef = dma_fence_get(&new_fence->base);
+
+	/* Attach new eviction fence to all BOs except pinned ones */
+	list_for_each_entry(mem, &process_info->kfd_bo_list,
+		validate_list.head) {
+		if (mem->bo->tbo.pin_count)
+			continue;
+
+		dma_resv_add_fence(mem->bo->tbo.base.resv,
+				   &process_info->eviction_fence->base,
+				   DMA_RESV_USAGE_BOOKKEEP);
+	}
+	/* Attach eviction fence to PD / PT BOs */
+	list_for_each_entry(peer_vm, &process_info->vm_list_head,
+			    vm_list_node) {
+		struct amdgpu_bo *bo = peer_vm->root.bo;
+
+		dma_resv_add_fence(bo->tbo.base.resv,
+				   &process_info->eviction_fence->base,
+				   DMA_RESV_USAGE_BOOKKEEP);
+	}
+
+validate_map_fail:
+	ttm_eu_backoff_reservation(&ctx.ticket, &ctx.list);
+	amdgpu_sync_free(&sync_obj);
+ttm_reserve_fail:
+	mutex_unlock(&process_info->lock);
+	kfree(pd_bo_list);
+	return ret;
+}
+
+int amdgpu_amdkfd_add_gws_to_process(void *info, void *gws, struct kgd_mem **mem)
+{
+	struct amdkfd_process_info *process_info = (struct amdkfd_process_info *)info;
+	struct amdgpu_bo *gws_bo = (struct amdgpu_bo *)gws;
+	int ret;
+
+	if (!info || !gws)
+		return -EINVAL;
+
+	*mem = kzalloc(sizeof(struct kgd_mem), GFP_KERNEL);
+	if (!*mem)
+		return -ENOMEM;
+
+	mutex_init(&(*mem)->lock);
+	INIT_LIST_HEAD(&(*mem)->attachments);
+	(*mem)->bo = amdgpu_bo_ref(gws_bo);
+	(*mem)->domain = AMDGPU_GEM_DOMAIN_GWS;
+	(*mem)->process_info = process_info;
+	add_kgd_mem_to_kfd_bo_list(*mem, process_info, false);
+	amdgpu_sync_create(&(*mem)->sync);
+
+
+	/* Validate gws bo the first time it is added to process */
+	mutex_lock(&(*mem)->process_info->lock);
+	ret = amdgpu_bo_reserve(gws_bo, false);
+	if (unlikely(ret)) {
+		pr_err("Reserve gws bo failed %d\n", ret);
+		goto bo_reservation_failure;
+	}
+
+	ret = amdgpu_amdkfd_bo_validate(gws_bo, AMDGPU_GEM_DOMAIN_GWS, true);
+	if (ret) {
+		pr_err("GWS BO validate failed %d\n", ret);
+		goto bo_validation_failure;
+	}
+	/* GWS resource is shared b/t amdgpu and amdkfd
+	 * Add process eviction fence to bo so they can
+	 * evict each other.
+	 */
+	ret = dma_resv_reserve_fences(gws_bo->tbo.base.resv, 1);
+	if (ret)
+		goto reserve_shared_fail;
+	dma_resv_add_fence(gws_bo->tbo.base.resv,
+			   &process_info->eviction_fence->base,
+			   DMA_RESV_USAGE_BOOKKEEP);
+	amdgpu_bo_unreserve(gws_bo);
+	mutex_unlock(&(*mem)->process_info->lock);
+
+	return ret;
+
+reserve_shared_fail:
+bo_validation_failure:
+	amdgpu_bo_unreserve(gws_bo);
+bo_reservation_failure:
+	mutex_unlock(&(*mem)->process_info->lock);
+	amdgpu_sync_free(&(*mem)->sync);
+	remove_kgd_mem_from_kfd_bo_list(*mem, process_info);
+	amdgpu_bo_unref(&gws_bo);
+	mutex_destroy(&(*mem)->lock);
+	kfree(*mem);
+	*mem = NULL;
+	return ret;
+}
+
+int amdgpu_amdkfd_remove_gws_from_process(void *info, void *mem)
+{
+	int ret;
+	struct amdkfd_process_info *process_info = (struct amdkfd_process_info *)info;
+	struct kgd_mem *kgd_mem = (struct kgd_mem *)mem;
+	struct amdgpu_bo *gws_bo = kgd_mem->bo;
+
+	/* Remove BO from process's validate list so restore worker won't touch
+	 * it anymore
+	 */
+	remove_kgd_mem_from_kfd_bo_list(kgd_mem, process_info);
+
+	ret = amdgpu_bo_reserve(gws_bo, false);
+	if (unlikely(ret)) {
+		pr_err("Reserve gws bo failed %d\n", ret);
+		//TODO add BO back to validate_list?
+		return ret;
+	}
+	amdgpu_amdkfd_remove_eviction_fence(gws_bo,
+			process_info->eviction_fence);
+	amdgpu_bo_unreserve(gws_bo);
+	amdgpu_sync_free(&kgd_mem->sync);
+	amdgpu_bo_unref(&gws_bo);
+	mutex_destroy(&kgd_mem->lock);
+	kfree(mem);
+	return 0;
+}
+
+/* Returns GPU-specific tiling mode information */
+int amdgpu_amdkfd_get_tile_config(struct amdgpu_device *adev,
+				struct tile_config *config)
+{
+	config->gb_addr_config = adev->gfx.config.gb_addr_config;
+	config->tile_config_ptr = adev->gfx.config.tile_mode_array;
+	config->num_tile_configs =
+			ARRAY_SIZE(adev->gfx.config.tile_mode_array);
+	config->macro_tile_config_ptr =
+			adev->gfx.config.macrotile_mode_array;
+	config->num_macro_tile_configs =
+			ARRAY_SIZE(adev->gfx.config.macrotile_mode_array);
+
+	/* Those values are not set from GFX9 onwards */
+	config->num_banks = adev->gfx.config.num_banks;
+	config->num_ranks = adev->gfx.config.num_ranks;
+
+	return 0;
+}
+
+bool amdgpu_amdkfd_bo_mapped_to_dev(struct amdgpu_device *adev, struct kgd_mem *mem)
+{
+	struct kfd_mem_attachment *entry;
+
+	list_for_each_entry(entry, &mem->attachments, list) {
+		if (entry->is_mapped && entry->adev == adev)
+			return true;
+	}
+	return false;
+}
+
+#if defined(CONFIG_DEBUG_FS)
+
+int kfd_debugfs_kfd_mem_limits(struct seq_file *m, void *data)
+{
+
+	spin_lock(&kfd_mem_limit.mem_limit_lock);
+	seq_printf(m, "System mem used %lldM out of %lluM\n",
+		  (kfd_mem_limit.system_mem_used >> 20),
+		  (kfd_mem_limit.max_system_mem_limit >> 20));
+	seq_printf(m, "TTM mem used %lldM out of %lluM\n",
+		  (kfd_mem_limit.ttm_mem_used >> 20),
+		  (kfd_mem_limit.max_ttm_mem_limit >> 20));
+	spin_unlock(&kfd_mem_limit.mem_limit_lock);
+
+	return 0;
+}
+
+#endif